Preheat your oven to 375°F (190°C) and line a 12-cup muffin tin with paper liners or grease each cup with cooking spray. Set out all ingredients and allow eggs to come to room temperature.
In a medium bowl, combine ½ cup flour, ⅓ cup brown sugar, and 1 tsp cinnamon, then cut in the cold butter pieces using a pastry cutter or fork until the mixture resembles coarse crumbs with pea-sized butter bits. Set aside.
Peel, core, and dice the apples into small ¼-inch pieces — you should have about 1½ cups. Set aside.
In a large bowl, whisk together the flour, baking soda, baking powder, salt, cinnamon, nutmeg, ginger, and cloves until evenly combined.
In a second large bowl, whisk together the pumpkin puree, granulated sugar, and brown sugar until smooth, then whisk in the oil, eggs one at a time, and vanilla extract.
Pour the wet ingredients into the dry ingredients and fold gently with a rubber spatula just until no dry flour streaks remain — the batter will be thick, and overmixing will make the muffins tough.
Gently fold the diced apples into the batter with a few strokes until evenly distributed.
Divide the batter evenly among the 12 muffin cups, filling each about ¾ full (roughly ⅓ cup of batter each), and smooth the tops lightly.
Sprinkle the streusel generously and evenly over each muffin, pressing down very lightly so it adheres to the batter.
Bake for 20–22 minutes, until a toothpick inserted into the center comes out clean or with just a few moist crumbs and the streusel is golden and crispy.
Let muffins cool in the tin for 5 minutes, then transfer to a wire rack and cool for at least 10 more minutes before serving.