In a shallow tray combine the flour, ground cinnamon, and brown sugar. Stir to combine. Pour in the melted butter and stir to make a paste. Spread the paste out on the bottom of the shallow tray and refrigerate.
½ cup all purpose flour, ½ teaspoon ground cinnamon, 4 Tablespoons brown sugar
Once the muffin batter is mixed and in the muffin tray, remove the tray from the fride. Sprinkle the white sugar over top and using your fingers crumble the mixture into small pebble size.
2 Tablespoons white sugar
Muffin Mix
Preheat the oven to 450℉/230℃.
In a bowl that is at least 2 cups, add the milk, egg, and vanilla extract. Whisk to combine. Add raisins and set aside.
¾ cup whole milk, 1 large egg, 1 Tablepsoon vanilla extract, 1 cup raisins
In a medium size mixing bowl combine flour, white and brown sugar, baking powder, ground cinnamon, and salt. Whisk to combine so all the ingredients are well combined.
1½ cups all purpose flour, ½ cup white sugar, ½ cup brown sugar, 2 teaspoons baking powder, 2 teaspoons ground cinnamon, ½ teaspoon fine grind sea salt
Pour the melted butter and oil to the bowl with the flour mixture and fold to combine. Add in the milk mixture with raisins and fold until the batter is a uniform consistency. Don't overmix the batter.
Line a 12-well standard muffin pan or two 6-well muffin pans with paper liners. Add 3 Tablespoons of muffin batter to each well. The batter should fill the liners about ⅔ full. If there is any leftover batter, equally divide it between the muffins. Top with 1 Tablespoon of the crumble.
Place the muffin pans in the preheated oven on the middle rack and bake at 450℉/230℃ for 5 minutes. Without opening the door of the oven, decrease the temperature to 350℉/175℃ for another 13 minutes. Remove from the oven and let cool for 5 minutes in the muffin pan and then remove and finish cooling on a cooling rack.