Apple Muffins

Method

1. Preheat the oven to 400°F (200°C). Grease a 12-cup muffin tin with baking spray or line with cupcake papers.
2. For the topping: in a medium bowl, stir together 55 g of the brown sugar, 60 g of the flour, 50 g of the granulated sugar and 1/2 tsp of the cinnamon. Melt 43 g of the butter and stir it in with a fork until the mixture is combined but still clumpy. Set aside.
3. For the muffins: in a medium mixing bowl, whisk together the remaining 240 g flour, the baking powder, the remaining 1 1/2 tsp cinnamon and the salt.
4. In another medium bowl, toss the diced apples with 2 tablespoons of the flour mixture until well coated.
5. In a large mixing bowl, beat the remaining 113 g softened butter with the remaining 110 g brown sugar and 100 g granulated sugar on medium speed until creamy, about 2 minutes. Add the eggs one at a time, beating until well combined. Scrape down the bowl and beat in the vanilla.
6. With the mixer on low speed, add a third of the flour mixture, followed by half of the milk. Continue alternating between the flour and milk, mixing just until combined. Fold in the apples. Divide the batter among the muffin cups, about 1/3 cup per muffin (they will be mostly full). Sprinkle the topping evenly over the batter, about 2 to 3 tablespoons per muffin.
7. Bake for 10 minutes.
8. Reduce the oven temperature to 350°F (175°C) and bake for 12 to 15 minutes more, or until a toothpick inserted into the center comes out with a few moist crumbs. Cool for 10 minutes in the pan, then move to a wire rack. Store in an airtight container at room temperature for up to 3 days.