Preheat oven to 400°F. Line a 12-cup muffin tin with paper liners or coat with nonstick spray. Set aside.
Crumb topping: combine sugars, cinnamon and salt in a medium bowl. Whisk in melted butter then add flour. Stir using a rubber spatula just until moist. The mixture will not look very crumbly yet. Spread out mixture on parchment paper to dry until crumbly ready to use.
Muffins: To make the muffins, in a large bowl, combine flour, sugar, baking powder, cinnamon, baking soda and salt.
In a separate medium bowl, whisk together milk, melted butter, vanilla and eggs. Pour mixture over the dry ingredients and stir using a rubber spatula until just incorporate, being careful not to overmix. Add the blueberries and gently mix to combine. Cover with a towel and let the batter rest for 15 minutes.
Scoop the batter evenly into the prepared muffin tins about 3/4 of the way full. Top with reserved crumb topping, using your fingers to gently press the crumbs into the batter to help it stay in place while baking. It will be a lot of crumb topping on each muffin. That's what you want!
Bake: Bake muffins in preheated oven for 10 minutes, then reduce the heat to 350 degrees and bake another 7-11 minutes
Remove from oven and allow to cool in muffin tin for 10 minutes then remove from pan and cool completely on wire rack.