Preheat the oven to 425°F. Line a 12 count muffin pan with paper liners.
In a small bowl, whisk together the all-purpose flour, baking powder, baking soda and salt. Set aside.
In a medium bowl, whisk the buttermilk, granulated sugar, vegetable oil, melted butter, brown sugar, eggs and vanilla extract until smooth and well combined.
Fold the dry ingredients into the wet ingredients until almost combined, leaving a few streaks of flour. Gently fold the blueberries and chocolate chips into the batter until just combined. Do not over mix!
Evenly divide the batter between muffin cups. If desired sprinkle with extra chocolate chips and/or blueberries.
Bake muffins at 425°F for 10 minutes then reduce the heat to 375°F and bake for 8 more minutes.
Notes
Weigh your ingredients using a kitchen scale! Measuring ingredients by volume is not accurate.
Butter: I recommend using unsalted butter. You can use salted butter, just be sure to omit the 1/2 tsp salt.
Store Blueberry Chocolate Chip Muffins in an airtight container for up to 4 days at room temperature.
Nutrition: the provided nutritional information is an estimate per serving. Please read my Nutrition Disclaimer for more information.