Preheat the oven to 400 degrees.
Next, you will brown the butter. Place 1/2 cup of butter in a sauce pan over medium heat. Let the butter melt and it will start to foam. Once the foam starts to disappear and clear bubbles appear, you will want to constantly whisk. The butter will begin to brown and you will notice it start to turn an amber color. Once the butter changes color, remove it from the stove and pour into a bowl. Set aside to use a little later in about 10 minutes.
You will now make the crumble topping. In a medium bowl, mix together the cinnamon, flour, and brown sugar. Then add in the melted butter and stir together with a fork. It will start to turn into a crumble. Cover the bowl with plastic wrap and place in the fridge.
Now for the muffin mix. In a bowl whisk together the flour, baking powder, and salt.
In a separate bowl, mix together the brown butter and sugar. Then, slowly add in each egg. You will then add in the vanilla extract, almond extract, and milk. Mix until all combined and smooth. Afterwards, slowly add in the flour mixture and stir with a wooden spoon. Be careful not to over mix.
In a separate bowl, add the blueberries and the 2 tbsp. of flour and mix together. This will help make sure the blueberries don't sink to the bottom. Gently fold in the blueberries to the mix.
Next, pour the batter into a muffin tin evenly. You can use liners or forego them, but I would recommend using them. Bake for 20 - 25 minutes, or until toothpick/tester comes out clean.