Preheat the oven to 425°F (220°C).

Cut the potatoes, zucchini, red onion, and cauliflower into bite-sized pieces.

Toss the vegetables with olive oil, salt, pepper, and dried herbs (such as thyme or rosemary) and spread them on a baking sheet.

Roast the vegetables in the preheated oven for 25-30 minutes, or until tender and golden brown.

Meanwhile, slice the halloumi cheese into thick pieces.

Heat a grill pan or skillet over medium-high heat and grill the halloumi slices until they are golden brown on both sides, about 2-3 minutes per side.

Once the vegetables are done roasting, transfer them to a serving plate.

Top with the grilled halloumi slices.

Serve immediately.