01 - Preheat the oven to 425°F. Line a baking sheet with parchment paper.
02 - Toss the broccoli florets with 2 tbsp olive oil, kosher salt, and black pepper until evenly coated. Spread in a single layer on the prepared baking sheet.
03 - Roast for 20–25 minutes, flipping the florets once halfway through, until the edges are golden and crisp-tender.
04 - While the broccoli roasts, heat 1 tbsp olive oil in a skillet over medium heat. Add the sliced almonds and toast, stirring constantly, for 2–3 minutes until golden brown.
05 - Add the minced garlic to the almonds and cook for 30 seconds, just until fragrant. Remove the skillet from heat.
06 - Stir the lemon zest, chopped parsley, Parmesan cheese (if using), and chili flakes into the almond mixture until well combined.
07 - Transfer the roasted broccoli to a serving platter and sprinkle generously with the toasted almond crumble. Serve immediately while warm.