Preheat the oven to 350º F. Spray a 12 count muffin tin with non-stick cooking spray or line with liners.
In a mixing bowl, whisk together flour, brown sugar, baking powder, salt, and cinnamon and mix until combined. Set aside.
In a separate bowl, combine eggs, apple cider, sour cream, and melted butter, and stir until just moistened. Set aside.
Melt 2 tablespoons butter in a skillet over medium-high heat. Add the apples and cook until softened, about 5-6 minutes. Sprinkle brown sugar, cinnamon, and salt. Cook for a few minutes until thick and bubbly. Set aside.
Slowly add the dry ingredients in batches, to the egg mixture, until fully combined. Then stir in the cooled apples, without over mixing. Pour the batter into the prepared muffin pan.
For the streusel topping, combine all of the ingredients until clumpy and flour is completely absorbed. Scatter evenly over muffins and transfer to the oven. Bake for 15-20 minutes, or until a toothpick inserted in center comes out clean. Enjoy!
