Preheat your oven to 400°F. Lightly grease a 12 cup muffin tin or line it with muffin liners.
Make the crumble topping first. In a medium bowl, whisk together the flour, brown sugar, and cinnamon. Add the cold butter and use your hands or a fork to mix until the texture is crumbly. Set it aside.
In a medium bowl, whisk together the flour, baking powder, baking soda, and salt.
In a large bowl, whisk together the Greek yogurt, sugar, eggs, vegetable oil, milk, and vanilla until smooth.
In a small bowl, toss the blueberries with ½ teaspoon of flour to help them stay evenly distributed.
Add the dry ingredients into the wet ingredients and gently stir until just combined. Do not overmix. Fold in the blueberries.
Use a ⅓ cup measure to divide the batter evenly into the muffin cups. Sprinkle the crumble topping over each one.
Bake for 17 to 20 minutes, until the tops spring back when lightly touched and a toothpick inserted in the center comes out clean.
Let the muffins cool in the pan for about 10 minutes, then move them to a wire rack to cool completely.