Print

Costco Chocolate Muffins

Costco chocolate muffins topped with chocolate chips, displayed on a wooden tray with a glass of milk.
Print Recipe

5 Stars 4 Stars 3 Stars 2 Stars 1 Star

No reviews

Bakery-style Costco chocolate muffins you can make at home—moist, jumbo, and loaded with rich chocolate flavor.

Ingredients

Scale
  • 1¾ cups all-purpose flour
  • ⅔ cup unsweetened cocoa powder
  • 1 Tbsp baking powder
  • 1 tsp baking soda
  • 1 tsp salt
  • 1 tsp espresso powder (optional)
  • ½ cup unsalted butter, melted and slightly cooled
  • 1¼ cups granulated sugar
  • 2 large eggs (room temperature)
  • 2 tsp vanilla extract
  • ¾ cup buttermilk (room temperature)
  • ½ cup sour cream (room temperature)
  • 2 cups semi-sweet chocolate chips (divided)

Instructions

  1. Preheat oven to 425°F and line a 6-count jumbo muffin pan with liners.
  2. In a medium bowl, whisk together flour, cocoa powder, baking powder, baking soda, salt, and espresso powder.
  3. In a large bowl, whisk melted butter and sugar. Add eggs one at a time, then vanilla extract, sour cream, and buttermilk. Mix until smooth.
  4. Fold in dry ingredients and 1½ cups of chocolate chips. Batter will be thick.
  5. Let batter rest for 10–15 minutes at room temperature.
  6. Divide batter into the muffin pan and top with remaining ½ cup chocolate chips.
  7. Bake at 425°F for 5 minutes, then reduce heat to 350°F and continue baking for 19–25 minutes.
  8. Cool in the pan for a few minutes before serving.

Notes

  • Use room temperature ingredients for better texture and rise.
  • Don’t overmix the batter to avoid dense muffins.
  • Can substitute sour cream with full-fat Greek yogurt.
  • Make your own buttermilk with milk and vinegar/lemon juice.
  • Store at room temp 2–3 days, refrigerated for 1 week, or freeze up to 3 months.

Nutrition

Find it online: https://recipeeasily.com/costco-chocolate-muffins-recipe/