Preheat oven to 400 degrees F. Combine the flour, poppy seeds, baking soda, baking powder, and salt together in a medium bowl. Mix and set aside.
In a large mixing bowl, add the eggs, oil, Greek yogurt, milk, sugar, lemon zest, lemon juice and vanilla extract. Whisk or beat together until smooth. Stir in the dry ingredients and mix until just combined.
To make the lemon crumb topping, combine the sugar, flour, brown sugar, lemon zest. Mix together. Add the butter and cut into the flour mixture using a pastry cutter, or fork, until it resembles course sand.
Divide the muffin batter into 12 muffin tins with muffin liners. Evenly top each muffin with the lemon crumb topping. Bake for 5 minutes at 400 degrees, then reduce heat to 350 degrees for 10-13 minutes more or until the batter is set. Let cool and enjoy!