01 -
In a medium bowl, mix together the grated lemon zest and granulated sugar. Rub them for a minute until it smells great. Then, whisk in the eggs until blended. Add in the Greek yogurt, vegetable oil, lemon juice, and vanilla extract until everything's smooth and pale yellow.
02 -
Keep aside 1/2 cup of blueberries for later. In a small bowl, toss the rest of the blueberries with a tablespoon of flour for a light coating. Gently fold these into the batter.
03 -
Put the muffins in the oven at 400°F (204°C) for 5 minutes. Then lower the temperature to 375°F (190°C) without peeking. Keep baking for another 13 to 15 minutes or until a toothpick poked in the center comes out clean.
04 -
Let the muffins sit in the pan for 5 minutes. Then move them to a wire rack to cool down completely.
05 -
Gently fold the wet ingredients into the dry mix until everything's just combined.
06 -
In a small bowl, combine the flour, sugar, and cinnamon. Use a fork to mix in the melted butter until crumbly. Chill this until you're ready for it.
07 -
Spoon the batter into muffin cups, filling them about two-thirds full. Tap the pan to level it. Scatter the reserved blueberries on top and sprinkle generously with the chilled streusel.
08 -
In a large bowl, mix together the flour, baking powder, and salt. Set this aside.
09 -
Heat your oven to 400°F (204°C) and line a muffin pan with paper liners. Put it aside.