Copycat Costco Double Chocolate Muffins
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Where are all my chocolate lovers? There’s nothing better than enjoying chocolate in the morning, and these bakery-style Double Chocolate Muffins are the perfect treat!
Just like my Copycat Costco Almond Poppyseed Muffins, these chocolate muffins let you skip the Costco membership and enjoy the infamous oversized muffins right at home. And dare I say they’re even better than the original??
Whether craving a decadent breakfast or sweet afternoon treat, these chocolate muffins deliver bakery-quality results right from your kitchen.
And if you love muffins as much as me, be sure to try my Lemon Poppyseed Muffins, Blackberry Muffins, Peanut Butter Muffins or French Toast Muffins!
Table Talk with Tawnie
The first time I tried one of Costco’s chocolate muffins, I was completely hooked. I mean it’s basically like getting to eat dessert for breakfast and who doesn’t love that?! So I knew after I nailed the Costco’s Almond Poppyseed Muffins for my copycat series, I had to try my hand at the chocolate ones! And I’m proud to say after many attempts, I’ve finally nailed this recipe! These muffins are moist, chocolatey, even better than the store-bought ones. I’ve also had trouble finding these at my Costco lately so I’m super happy I can make them at home whenever the craving strikes!
- Flour: I like to use all-purpose flour for the perfect muffin texture. Be sure to spoon and level the flour to avoid adding too much, which can make the muffins dense.
- Cocoa powder: I used regular unsweetened cocoa powder for these muffins! If you really want to amp up the chocolate flavor, you could try the Special Dark cocoa powder.
- Baking Powder and Baking Soda: This combination helps create a high-rise and fluffy texture. Ensure the ingredients are fresh (not expired), as old leavening agents won’t give the same lift.
- Espresso powder: Espresso powder is optional but helps to enhance and intensify the chocolate flavor of these muffins. But don’t worry—they’ll still be delicious if you skip it.
- Sour cream: I love adding sour cream to my muffins and cakes. It helps the muffins stay extra moist and rich. Substitute: full-fat Greek yogurt works as a great alternative.
- Buttermilk: In my testing, I found buttermilk (as opposed to milk) gives the muffins a softer texture and an even better flavor.
- Chocolate chips: For these muffins, I used semi-sweet chocolate chips (they’re my go-to for baking), but feel free to use milk chocolate or dark chocolate chips if you prefer.
Step by Step Directions
(For the full recipe, scroll down to the recipe card below)
Stir together dry ingredients
Whisk together the dry ingredients!
Combine butter and sugar
Whisk together the butter and sugar first.
Add remaining wet ingredients
Then add add the rest of the wet ingredients and stir until combined!
Combine ingredients and bake
Combine all the ingredients, divide into muffin tin and bake!
Enjoy!
Then enjoy a warm muffin with nice cold glass of milk! 🥛
Expert Tips
- Don’t overmix the batter: Overmixing can lead to tough muffins. Mix your batter until the dry ingredients are incorporated into the wet and there are no dry spots left.
- Room-temperature ingredients: Always make sure your wet ingredients, like eggs, sour cream, and buttermilk, are at room temperature before mixing. I like to sit my ingredients out about 30 minutes to an hour before baking. The reason we want room-temperature ingredients is that the cold ingredients can cause the batter to seize, leading to tougher muffins.
- Measure flour: To avoid dry and dense muffins, always spoon your flour into a measuring cup and level it off. Dipping your measuring cup straight into the bag or container of flour can pack too much flour than the recipe calls for. You can also use a food scale if you have one for the exact measurement.
- Fill the muffin liners almost to the top: To get those big, bakery-style muffin tops, fill the muffin liners to the top. This recipe will make 8 jumbo muffins.
- Bake at a Higher Temperature First for a Better Rise: For my muffins, I like to start the bake time at a higher temperature to help puff up the top, creating that iconic dome look. Then, I reduce the temperature to allow the muffins to fully bake through without overbaking.
Variations / Substitutions
- Gluten-free: Use a 1:1 gluten-free flour blend instead of all-purpose flour. Add ½ tsp. xanthan gum if your flour blend doesn’t already include it.
- Chocolate chips: Swap the semi-sweet chocolate chips for milk chocolate chips (sweeter) or dark chocolate chips (less sweet option). You can also try white chocolate chips for contrast and extra sweetness.
- Nuts: Add chopped walnuts, pecans, or almonds for extra crunch.
- Cocoa powder: Use Dutch-processed cocoa for a deeper, richer chocolate flavor.
Storage / Freezing
- Storage: Store double chocolate muffins at room temperature in an airtight container for 2–3 days. You can also place in the refrigerator for up to 1 week.
- Freeze: Let muffins cool completely, then individually wrap and freeze for up to 3 months—just thaw or warm in the microwave before eating!
FAQs
Can I make standard-sized muffins with this recipe?
Yes. For standard-size muffins baked in a 12-count muffin pan, reduce baking time to about 20 total minutes: 5 initial minutes at 425°F and ~12 minutes at 350°F. You will get ~14 muffins.
Why did my muffins sink in the middle?
There could be several reasons your muffins sank in the middle:
✔ Overmixing the batter—too much air can cause collapse.
✔ Underbaking—test with a toothpick; it should come out clean or with a few crumbs.
✔ Opening the oven door too early—this causes temperature fluctuations.
Why are my muffins sticking to the liners?
Be sure to use high-quality parchment liners (cheaper ones tend to stick). Let muffins cool for 10 minutes before peeling off the liner. You can also lightly spray the liners with nonstick cooking spray before filling.
Does the espresso powder make these muffins taste like coffee?
No, the espresso powder will not make these muffins taste like coffee! Espresso powder is like a secret baking weapon for any type of chocolate baked goods as it simply helps to enhance and intensify the chocolate flavor. I highly recommend grabbing some if you bake frequently, but it’s not required, and your muffins will still be delicious if you decide to omit.
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Copycat Costco Double Chocolate Muffins
Ingredients
- 1 3/4 cups all-purpose flour (spooned and leveled )
- 2/3 cup unsweetened cocoa powder (sifted if clumpy)
- 1 Tbsp. baking powder
- 1 tsp. baking soda
- 1 tsp. salt
- 1 tsp. espresso powder (optional)
- ½ cup butter, unsalted (melted and slightly cooled )
- 1 ¼ cup granulated sugar
- 2 large eggs (room temperature)
- 2 tsp. vanilla extract
- 3/4 cup buttermilk* (room temperature )
- 1/2 cup sour cream (room temperature)
- 2 cups semi-sweet chocolate chips (divided)
Last step! If you make this, please leave a review and rating letting us know how you liked this recipe! This helps our business thrive & continue providing free recipes.
Instructions
- Preheat and prep: Preheat oven to 425°F and line a 6-count jumbo muffin pan with jumbo muffin liners. Set aside. (Note: you can make smaller muffins in a regular sized muffin tin. See recipe notes).
- Whisk dry ingredients: In a medium-sized mixing bowl, whisk together the flour, cocoa powder, baking powder, baking soda, salt, and espresso powder (if using). Set aside.1 3/4 cups all-purpose flour, 2/3 cup unsweetened cocoa powder, 1 Tbsp. baking powder, 1 tsp. baking soda, 1 tsp. salt, 1 tsp. espresso powder
- Melted butter & sugar: Whisk the slightly cooled melted butter and sugar in a large mixing bowl.½ cup butter, unsalted, 1 ¼ cup granulated sugar
- Add wet ingredients: Add eggs in one at a time, followed by the vanilla extract. Then add the sour cream and buttermilk, whisk.2 large eggs, 2 tsp. vanilla extract, 1/2 cup sour cream, 3/4 cup buttermilk*
- Add dry ingredients: Fold in the dry ingredients and 1 ½ cup chocolate chips. (Reserve the other ½ cup for topping on the muffins). Careful not to over mix. The batter will be very thick. Allow the batter to rest for 10-15 minutes at room temperature.2 cups semi-sweet chocolate chips
- Scoop into muffin pan: Divide the batter into the prepared jumbo muffin pan then top muffins with reserved chocolate chips. You should get 6 jumbo muffins, but if you feel like the batter is getting too close to the tops, make a couple small/regular sized muffins to avoid spilling over the edges.
- Bake: Bake for 5 min at 425°F, then reduce oven temperature to 350°F (without opening the oven) and bake again for ~19-25 minutes. Try not to open the oven door too much or too early, as this can cause temperature fluctuations and the centers may sink. (Also, ovens vary. You'll know the muffins are done when they have risen and a toothpick inserted in the center has a few moist crumbs attached, but nothing wet or goopy). Careful not to overbake these beauties!
- Cool and enjoy: Cool in the muffin pan for a few minutes, then enjoy!
Video
Notes
- Room Temperature: 2–3 days in an airtight container.
- Refrigerated: Up to 1 week in an airtight container.
- Frozen: 2–3 months wrapped tightly in plastic wrap and stored in a freezer-safe bag or container.
Nutrition Information
Nutritional information is provided as a courtesy and is automatically calculated. It should only be construed as an estimate rather than a guarantee. Ingredients can vary and Kroll’s Korner can’t make any guarantees to the accuracy of this information.
📸 Photography by Creating Kaitlin
So fudgy and delicious! Super easy to follow recipe.
Thank you Elizabeth! So happy you enjoyed them 🙂