Pre-heat oven to 375 F/180 C. Lightly oil a 6-cup standard muffin tin or coat with nonstick spray.: The warm oven helps the cups crisp quickly, and lightly oiling the muffin tin ensures the edges release easily while promoting golden browning. When the oven is at the correct heat you will notice a steady dry warmth and a faint smell of heated metal, which signals readiness. Use a small brush or a paper towel to spread a thin, even layer of Extra-virgin olive oil so the bottoms do not stick. A frequent mistake is using too much oil, which causes pooling and sogginess instead of crisping.
In a large pot of boiling water, blanch each lasagna sheet for 2-3 min until slightly softened. Repeat with the remaining lasagna sheets.: Blanching makes the lasagna sheets pliable enough to shape without tearing, and you should see them become translucent at the edges while still holding body. The water should be at a lively boil so the sheets soften quickly, you will hear a gentle rolling sound and see small crowded bubbles. After blanching, lay them flat on a clean surface to cool briefly. Be careful not to overcook because over softened sheets will fall apart when you try to mold them into the tin.
Fit each lasagna sheet carefully into the cupcake mould, making sure not to break it.: As you press the slightly cooled sheet into each cup, feel for even coverage along the sides and bottom so the filling is supported. The sheet should tuck in with a soft tug and create thin walls that will crisp when baked. If the sheet resists, let it rest a moment longer to avoid tearing. One common error is forcing a brittle sheet too early, which causes holes and leaks in the final bake.
In a small bowl, mix together the ricotta with the basil leaves, and season with salt and pepper to taste. Transfer the ricotta into a piping bag or use a spoon. Fill each lasagna cup with 1 tablespoon of the ricotta filling.: The aroma of chopped basil leaves folded into the ricotta cheese is fresh and herbaceous, it lifts the mild dairy note with green brightness. Use a spoon or piping bag for even distribution so each cup receives a consistent amount. Texturally, the ricotta should be creamy and slightly grainy, not watery. If it feels loose, let it drain more; excessive moisture will prevent the cups from setting and may cause a watery mouthfeel.
Add 1-2 tablespoon of marinara sauce in each lasagna cup to cover the ricotta mixture.: Spoon the marinara sauce over the ricotta so it nestles and creates a thin tomato layer. You want the sauce to add acidity and color without overwhelming the creamy center. The heat will coax the sauce aromatics forward and you will notice a sweet tomato scent as it warms. Avoid adding too much sauce, which can make the base soggy and mute the ricotta.
Top each lasagna cup with a small amount of cubed mozzarella.: Scatter the finely cubed mozzarella across each cup so it melts into stringy, golden pockets. Small cubes help the cheese warm uniformly and form attractive molten spots. When the cheese begins to melt in the oven it will bubble gently and develop a light golden hue. Putting too-large pieces risks uneven melting, leaving some bites under gooey and others untouched.
Drizzle with a little olive oil and season with black pepper to taste.: A light drizzle of Extra-virgin olive oil gives shine and encourages the edges to brown while a crack of pepper adds warmth. The oil will carry aromatics into the crust, and you will notice a subtle fruity scent from the oil as it warms. Don’t over oil, excess will pool and make the cups greasy, diminishing the crisp contrast.
Bake the lasagna cups for 10-12 minutes, or until the cheese has melted and the lasagna cups are cooked through and crispy golden brown.: During baking, the kitchen will fill with a warm, cheesy aroma and you will hear small pop sounds as pockets of moisture evaporate. Look for bubbling cheese and edges that turn a rich golden brown, that is the visual cue indicating crispness. The short bake preserves creamy interiors while creating crunchy rims. A common mistake is underbaking which leaves the cheese unmelted, or overbaking which dries the ricotta out.
Serve immediately, garnished with basil leaves.: Serving while hot ensures that the mozzarella is stretchy and the edges remain crisp, and the fresh basil leaves on top add an herbaceous finish. The contrast of hot interior and cool herb is delightful in the mouth. If you let them sit too long they soften and lose the memorable textural contrast.