1. Avoid over measuring the flour. 2. Use cold butter for the streusel. 3. Don't over-mix the batter 4. Try not to over fill the muffin tin
Cut the butter into the dry ingredients until fully incorporated and crumbly.
Start making the muffins by combining the dry ingredients.
Add oil, sugars, egg, vanilla extract and sour cream to a large mixing bowl and whisk to combine.
Add the dry ingredients to the wet ingredients and gently stir. Do not over mix!
Use a spatula to fold the blueberries into the batter evenly.
Fill each muffin cup about 3/4 full. You should have enough batter for 12 muffins!
Divide the streusel among the 12 muffins and you're ready to bake!
Bake the blueberry muffins for 15-20 minutes, or until a toothpick inserted into the middle comes out clean.
Allow the muffins to cool in the pan for 3-5 minutes, then transfer them to a cooling rack.
You can enjoy these delicious muffins a little warm or at room temperature. Either way, they're absolutely perfect!