Costco Chocolate Muffins

Costco Chocolate Muffins are known for their rich, chocolatey flavor, moist texture, and generous size. This homemade version captures all the indulgence of the store-bought favorite, packed with chocolate chips in every bite. Perfect for breakfast, dessert, or a sweet snack, these muffins are sure to satisfy any chocolate lover’s cravings.

Why You’ll Love This Recipe

These muffins are moist, soft, and loaded with chocolate chips, offering bakery-style results right from your kitchen. The sour cream ensures a tender crumb, while the cocoa powder and chocolate chips deliver deep chocolate flavor. They’re simple to make, freeze well, and are ideal for sharing or meal prepping for the week.

Ingredients

(Tip: You can find the complete list of ingredients and their measurements in the recipe card below.)

2 and 2/3 cups all-purpose flour
2 teaspoons baking powder
1/2 teaspoon baking soda
1 teaspoon kosher salt
3/4 cup unsweetened cocoa powder
1/2 cup hot water
1 cup granulated sugar
1/3 cup vegetable oil
2 large eggs plus 1 egg yolk
2 teaspoons pure vanilla extract
3/4 cup sour cream
15 ounces semi-sweet chocolate chips

Directions

1. Preheat oven to 375°F (190°C). Line a muffin tin with paper liners.

2. In a bowl, whisk together flour, baking powder, baking soda, and salt.

3. In a separate bowl, whisk cocoa powder and hot water until smooth.

4. Add sugar, oil, eggs, vanilla extract, and sour cream to the cocoa mixture. Whisk until well combined.

5. Gradually fold the dry ingredients into the wet mixture until just combined. Do not overmix.

6. Gently stir in the chocolate chips.

7. Divide the batter evenly among muffin cups, filling each almost to the top.

8. Bake for 18–20 minutes, or until a toothpick inserted in the center comes out with moist crumbs.

9. Cool in the pan for 5 minutes, then transfer to a wire rack to cool completely.

Servings and timing

This recipe makes 12 large muffins.
Prep time: 15 minutes
Baking time: 20 minutes
Total time: 35 minutes
Approximate calories: 450 kcal per muffin

Variations

• Double chocolate: Use dark chocolate chips for an even richer flavor.

• Mini muffins: Make mini versions by baking for 10–12 minutes.

• Nutty addition: Stir in 1/2 cup chopped walnuts or pecans.

• Mocha flavor: Add 1 teaspoon instant espresso powder to the cocoa mixture.

• Gluten-free: Use a 1:1 gluten-free flour blend in place of all-purpose flour.

Storage/Reheating

Store muffins in an airtight container at room temperature for up to 3 days, or in the refrigerator for up to 5 days. For longer storage, freeze muffins in a sealed container or freezer bag for up to 2 months. Thaw at room temperature or microwave for 15–20 seconds before serving.

FAQs

Can I use buttermilk instead of sour cream?

Yes, buttermilk can be used, though the batter will be thinner, and the texture slightly lighter.

Can I use milk chocolate chips?

Yes, but the muffins will be sweeter and less rich than with semi-sweet chips.

How do I make these muffins extra moist?

Be careful not to overbake, and ensure the sour cream is at room temperature for best mixing.

Can I make jumbo muffins with this recipe?

Yes, adjust baking time to about 25–28 minutes and fill jumbo liners nearly to the top.

Why is there an extra egg yolk in the recipe?

The extra yolk adds richness and helps create a moist, tender crumb.

Can I make this batter ahead of time?

It’s best to bake right after mixing, but you can refrigerate the batter for up to 12 hours before baking.

How do I get a domed muffin top?

Fill the cups nearly full and bake at the higher temperature of 375°F (190°C) to help create a rise.

Can I add fruit to these muffins?

Yes, try adding 1/2 cup raspberries or chopped cherries for a fruity twist.

Is vegetable oil necessary, or can I use butter?

Oil helps keep the muffins moist, but melted butter can be used for a slightly different texture.

Can I use Dutch-processed cocoa powder?

Yes, Dutch-processed cocoa will work and provide a deeper chocolate flavor.

Conclusion

Costco Chocolate Muffins are a delicious homemade treat that rivals the bakery original. Moist, chocolate-packed, and easy to make, they are perfect for breakfast, snacks, or dessert. Whether enjoyed fresh from the oven or stored for later, these muffins are sure to become a family favorite.