Preheat your oven to 220°C (430°F). Line a baking sheet with parchment paper or a non-stick mat to keep things easy and prevent sticking.
Trim the woody ends off the asparagus, about 1-2 inches from the bottom, until you have tender, straight stalks.
Place the trimmed asparagus on the baking sheet and drizzle with olive oil. Toss gently to coat each spear evenly; this helps them roast beautifully and develop flavor.
Spread the asparagus in a single layer, making sure they aren’t overcrowded. This ensures crispy edges and even roasting.
Roast in the oven for about 12-15 minutes, shaking the pan once halfway through, until the tips are blistered and the stalks are tender and vibrant green.
While the asparagus roasts, thinly slice the garlic cloves. Keep a close eye on them later so they don’t burn—burnt garlic turns bitter and ruins the aroma.
When the asparagus has about 3 minutes left, sprinkle the sliced garlic evenly over the spears and return to the oven. Roast until fragrant and just starting to turn golden, about 3 minutes.
Remove the baking sheet from the oven and immediately sprinkle the hot asparagus with freshly grated Parmesan cheese. The heat will melt the cheese into crispy bits and add a lovely savory flavor.
Finish with a pinch of flaky sea salt and, if desired, a squeeze of lemon for brightness. Serve immediately to enjoy the crispy cheese and tender, flavorful asparagus.