Preheat the oven: Set to 425°F (220°C). High heat is essential for browning and crisp edges.
Prep the pan: Line a large sheet pan with parchment for easy cleanup.
If using two pans, even better—crowded veggies steam instead of roast.
Cut the vegetables: Aim for similar sizes so they cook evenly. Dense veggies like carrots and potatoes should be cut smaller than softer ones like zucchini.
Make the garlic butter: Melt butter gently. Stir in olive oil, minced garlic, chopped parsley, lemon zest, a pinch of red pepper flakes, salt, and pepper.
Toss to coat: In a large bowl, add the veggies and pour over most of the garlic butter.
Toss well so everything gets a thin, even coating.
Arrange on the pan: Spread the vegetables out in a single layer with some space between pieces. Place cut sides down for maximum browning.
Roast the veggies: Bake for 20 minutes. Stir or flip, then roast another 10–15 minutes, until edges are caramelized and centers are tender.
Finish with flavor: Drizzle the remaining garlic butter over the hot veggies.
Squeeze on a little lemon juice and sprinkle more parsley.
Optional toppings: Add grated Parmesan for richness, or a light drizzle of balsamic reduction for sweetness and tang.
Serve hot: Enjoy as a side with chicken, salmon, steak, or grains. It’s also great piled over quinoa or tossed with pasta.