Preheat the oven to 400°F/200°C and line a rimmed baking sheet with parchment paper.
Fill a pot of water with a few inches of water and fit it with a steamer attachment. Bring the water to a boil and add the florets to the steamer. Steam the broccoli florets for 4-5 minutes, or until they're tender and can be pierced pretty easily with a fork, but not mushy. Remove the steamer basket from heat.
Transfer the florets to a flat surface that has been lined with tea towels or paper towels. Pat the florets very dry. Transfer them to the parchment-lined baking sheet.
Use the bottom of an average, flat-bottomed drinking glass or mason jar to smash the florets until they are considerably flattened, but not broken or falling apart. They should be 1/4-1/2 inch (6mm-1.3cm) thick. If they release any additional moisture when you smash them, use a paper towel to pat them dry again on the baking sheet. The smashed florets should be as dry as possible.
Whisk the oil, garlic powder, and salt together in a small bowl. Use a pastry or basting brush to brush this mixture over the tops of the florets, coating them quite well. Add crushed red pepper flakes or freshly ground black pepper as desired.
Transfer the broccoli to the oven and bake for 15-18 minutes, or until the florets are sizzling and turning golden. Remove the sheet from the oven and add finishing seasonings as desired: a squeeze of lemon juice and sprinkle of lemon zest, or a few tablespoons of cashew parmesan, sprinkled over the florets.
Return the florets to the oven and bake for 5-7 more minutes, or until the florets are crispy and browning at the edges. If you like, finish them with one final sprinkle of salt and/or an extra drizzle of olive oil. Enjoy.
Notes
Alternatively, use a 12-16 ounce / 340-450g bag of frozen broccoli florets. Instead of steaming as described, cook the florets from frozen as directed on the package. Then proceed with the recipe as written.