Transfer the cottage cheese into a microwave-safe bowl or ramekin.
Add the garlic powder and half of the Italian seasoning to the cottage cheese and stir until well combined.
Smooth the top of the cottage cheese with a spoon and spread the marinara sauce evenly over the surface.
Distribute the shredded mozzarella cheese over the marinara layer.
Arrange the pepperoni slices on top of the mozzarella.
Microwave on high power for 90 to 120 seconds, checking at the 60-second mark, until the cottage cheese is warm and the mozzarella is fully melted and bubbly.
Garnish with the remaining Italian seasoning, red pepper flakes, and Parmesan cheese if using.
Allow the bowl to rest for 60 seconds to set before serving.