Drain the sprouts very well. Put the Brussels sprouts on a paper towel and then pat very dry with a second paper towel. Transfer to a bowl. Toss with olive oil, salt, red pepper flakes, and black pepper. Then toss in the Parmesan cheese and lemon juice.
2 tablespoons olive oil, 1 teaspoon kosher salt, 1/4 teaspoon red pepper flakes, dash freshly ground black pepper, 1/4 cup Parmesan cheese, 1 tablespoon lemon juice