Preheat the oven to 425º F. Line a baking sheet with parchment paper.
Trim the ends and any ratty leaves from the Brussels sprouts. Slice the larger ones in half leaving the smaller ones whole. Place on the prepared baking sheet then toss with the olive oil, salt, and pepper. Arrange in a single layer on the baking sheet - cut side down.
Place in a pre-heated oven for ~18-22 minutes until tender with crispy edges. Check after ~12 minutes by flipping one over and piercing it with a fork - roast for longer as required. Oven temperatures vary greatly
Remove from the oven. Toss the roasted Brussels sprouts with S&P, lemon juice, parmesan cheese, red pepper flakes (and any other toppings). Taste and adjust seasoning as needed.
Serve immediately with Nana's sauce.
Topping Options: For extra crunch, add a handful of toasted pine nuts, almonds or hazelnuts or a sprinkle of pomegranate seeds. Add some parmesan cheese or vegan feta cheese for extra creaminess.