Cut head of broccoli into bite-sized florets (you should end up with around 6 cups). If using, slice stalk into 1/2-inch pieces, or save for another use. (Note: the stalk won't become as tender as the florets, however it's a great source of prebiotics and is delicious roasted!)
Heat oil in a large skillet with a fitted lid over medium-high. Once oil is shimmering, add broccoli, and season with salt and pepper. Toss to combine and cook, uncovered, 1 minute.
Cover and continue cooking, lifting lid to stir every 1 to 2 minutes to prevent burning, until crisp-tender and lightly charred, about 8 minutes total. Stir in garlic powder and lemon juice, and remove from heat.