Preheat oven to 350 degrees and line or grease a 12 cup muffin tin.
Mix 2 cups flour, baking powder, and lemon zest in a large bowl.
Whisk together granulated sugar and egg until well combined.
Add Greek yogurt, oil, buttermilk, and lemon juice to sugar mixture and combine.
Add wet ingredients to the dry ingredients and fold until they're combined.
Combine blueberries and remaining tablespoon of flour together in a small bowl.
Fold floured blueberries into the batter.
Fill each of the muffin cups with batter until they're about 2/3 full.
Top each muffin with 2 teaspoons streusel topping.
Bake for 18-20 minutes or until a toothpick inserted into the center comes out clean.
Remove muffins from muffin tin and allow to cool of a wire rack before eating.
Combine all ingredients in a medium-sized bowl with a fork or your fingers until the mixture resembles wet sand.
Store in an airtight container in the fridge for up to five days. Then if you have any leftover, freeze in a freezer safe container and reheat individually as desired.Allow muffins to come to room temperature before eating or reheat in the microwave or warm quickly in the oven before enjoying.Ingredient Notes:
Oil – you can use any type of flavorless oil in this recipe. I typically use avocado but vegetable works as well, just don’t use something that has a strong flavor like olive oil or coconut oil.
Buttermilk – if you don’t have actual buttermilk, you can combine 1/2 TBS of either white vinegar or lemon juice with enough milk to get to 1/2 cup. Mix it together then let it sit for 10 minutes to sour and use that in place of the buttermilk.
Greek yogurt – you can use either vanilla or plain Greek yogurt for this recipe. I like to use vanilla for a little bit of added flavor but plain works as well. If you do use plain, add 1/2 tsp of vanilla to the wet ingredients to still get the vanilla flavor.
Lemon juice/zest – these muffins have just a small hint of lemon, if you really want to taste the lemon flavor (like in this lemon poppy seed bread), I recommend using 1 TBS lemon juice and a full tsp of lemon zest to amp up the citrus flavor.