Preheat oven to 400°F (200°C) and line a baking sheet with parchment paper.
Place split English muffins cut-side up on the prepared baking sheet and toast in the oven for 3 minutes to prevent sogginess.
Remove from oven and brush the cut side of each muffin lightly with olive oil.
Spread approximately 1 tablespoon of pizza sauce onto each muffin half.
Distribute the shredded mozzarella cheese evenly over the sauce.
Add mini pepperoni slices and a sprinkle of dried oregano to each pizza.
Return to the oven and bake for 8 to 10 minutes until the cheese is melted and beginning to brown.
Remove from oven and allow to rest for 2 minutes before serving.