Preheat your oven to 425°F and line a large sheet pan with parchment paper. This temperature matters because it's hot enough to create caramelized edges without scorching the delicate pepper skin—I learned this the hard way after two burnt batches last summer.

Wash and cut your bell pepper into one-inch chunks, discarding seeds. Dice your zucchini and yellow squash to match that size, then slice your red onion into pieces that won't fall through the rack.

Mince your garlic finely and add it to a small bowl with olive oil, salt, black pepper, oregano, and smoked paprika. Whisk it together for 30 seconds until the spices start to release their fragrance—this prevents the garlic from burning alone on the pan.

Toss all your vegetables with the oil mixture until everything's lightly coated, spreading them in a single layer across your sheet pan. Leave a little space between pieces so they roast instead of steam, which is the difference between soggy sides and the crispy-edged versions that actually taste like summer.

Roast for 28 to 30 minutes, stirring halfway through at the 15-minute mark. I confess I often forget this step, but when I remember, the results are noticeably more even—you'll see the edges starting to turn golden brown, and that's your signal everything's done.

Remove from the oven and taste one piece before serving. If the vegetables feel soft inside but hold their shape, they're perfect—if they're still firm, give them another 3 to 5 minutes.