Preheat the oven to 375°F (190°C). Lightly oil a 6-cup muffin tin or spray with nonstick spray.
Bring a large pot of salted water to a boil. Blanch each lasagna sheet 2–3 minutes until pliable but not fully cooked, then remove and drain.
Fit each softened lasagna sheet into a muffin cup, pressing down gently to form a cup shape; avoid tearing the pasta.
In a small bowl, finely chop most of the basil leaves and stir into the drained ricotta. Season with salt and pepper to taste.
Transfer the ricotta mixture to a piping bag or use a spoon and fill each lasagna cup with about 1 tablespoon of ricotta filling.
Spoon 1–2 tablespoons marinara sauce over the ricotta in each cup to cover the filling.
Top each cup with a small amount of the cubed mozzarella, drizzle lightly with olive oil, and season with black pepper.
Bake for 10–12 minutes until the cheese melts and the pasta edges turn golden and slightly crisp.
Remove from the oven, let cool 1–2 minutes, then garnish with remaining basil leaves and serve immediately.
