**Preheat Oven:** Preheat your oven to 425°F (220°C) and line a baking sheet with parchment paper or a silicone mat.
**Prepare Broccoli:** In a large mixing bowl, toss the broccoli florets with olive oil, garlic powder, salt, and black pepper until evenly coated.
**Roast Broccoli:** Spread the broccoli onto the prepared baking sheet in a single layer. Roast for 15 minutes or until tender.
**Smash Broccoli:** Remove the baking sheet from the oven. Using a potato masher or fork, gently press down on each floret to flatten slightly.
**Add Toppings:** Sprinkle the smashed broccoli with grated parmesan cheese and panko breadcrumbs, if using.
**Bake Again:** Return the baking sheet to the oven and bake for an additional 10–12 minutes, or until the cheese is melted and golden.
**Serve:** Serve immediately with a squeeze of fresh lemon juice for added brightness.