Preheat oven to 375 degrees F (190 degrees C). Line 9 muffin cups with paper muffin liners.
Whisk 1 1/2 cups sifted flour, white sugar, brown sugar, pumpkin pie spice, baking powder, and salt together in a large bowl. Stir pumpkin puree, vegetable oil, milk, egg, vanilla extract, and lemon extract together in another bowl.
Pour pumpkin puree mixture into flour mixture; stir until batter is just combined.
Stir white chocolate chips and 1 tablespoon flour together in a bowl until chips are coated. Fold chips into batter; spoon batter into prepared muffin cups.
Bake in the preheated oven until a toothpick inserted into the center of a muffin comes out clean, 15 to 20 minutes.