In a large bowl put flour, baking powder and salt. Sift together.
Make a well in center of dry ingredients. Add in milk and vanilla. Stir just until moistened, batter will be lumpy.
In another bowl cream butter and sugar, add in egg and beat until smooth. Gently mix into the flour mixture.
Gently fold blueberries into batter.
Fill greased muffin cups with 1/3 cup batter.
Add streusel topping (see below) if desired.
Bake in 400 degreen oven for 20-25 minutes until nicely browned.
After you remove them from the oven loosen around the edges and push streusel topping that has spread onto the muffin tin back onto the muffin .
The streusel topping hardens as it cools and it can make it difficult to remove from the pan.
I just run a toothpick around the edge, pushing the streusel topping off of the pan and onto the muffin
Streusel Topping:
In small bowl rub sugar, flour and butter until crumbly
Sprinkle muffin with topping prior to baking
Notes
Don’t Overmix the Batter. Stir the wet and dry ingredients together just until combined. A few small lumps are fine. Overmixing develops the gluten in the flour and can make your muffins tough instead of tender.
Fresh or Frozen Blueberries Work. Fresh blueberries are wonderful when they’re in season, but frozen berries work well too. If using frozen blueberries, let them thaw and drain before adding them to the muffin batter.
Coat Frozen Blueberries in Flour. After thawing and draining frozen blueberries, give them a light coating of flour before folding them into the batter. This helps prevent the blueberries from bleeding quite as much into the muffin batter.
Fold in the Blueberries Gently. Use a spatula to gently fold the berries into the batter so you don’t crush them. This is especially important with thawed frozen blueberries, which are softer than fresh berries.
Don’t Overfill the Muffin Cups. Fill each muffin cup about 2/3 full so the muffins bake at the same rate. A cookie scoop works great for portioning out the batter without making a mess.
Don’t Skimp on the Streusel. Sprinkle the crumb topping generously and evenly over each muffin before baking. You want some of that buttery, sugary goodness in every bite.
Check for Doneness. Insert a toothpick into the center of a muffin. It should come out clean or with just a few moist crumbs attached. Be careful not to overbake, which can dry out your blueberry muffins.
The streusel topping hardens as it cools and it can make it difficult to remove from the pan. If you have any problem getting the muffins out run the point of a sharp knife or a toothpick around the edge of the muffin to help loosen it.