Preheat and prep: Preheat your oven to 220°C (425°F). While the oven heats, peel and cube the potatoes into roughly 1-inch pieces so they cook evenly. Cutting to uniform size ensures even cooking and consistent crisping later.

Parboil the potatoes: Place the cubed potatoes in a large pot and cover with cold water by 1 inch; add 1 tsp salt. Bring to a simmer and cook for 8–10 minutes until a paring knife slides into a cube with slight resistance (not fully cooked). Parboiling starts the cooking process so the interior becomes tender without over-browning the exterior when you roast.

Dry and roughen: Drain the potatoes thoroughly and return them to the hot pot for 30–60 seconds to let surface moisture evaporate. Shake the pot lightly or use the back of a spoon to rough up the edges of the cubes — the tiny fractures will become extra-crispy when roasted.

Season and first roast: Toss the potatoes with 2 tbsp olive oil, 1/2 tsp salt, 1/4 tsp black pepper, and 1/2 tsp smoked paprika in a bowl. Spread into a single layer on a rimmed baking sheet and roast at 220°C (425°F) for 25–30 minutes, turning once halfway through, until edges are golden and crisp. High direct heat and a thin layer of oil create Maillard browning for that blistered restaurant finish.

While potatoes roast — char the pepper: Place the whole bell pepper directly over a gas flame, under a broiler, or on a very hot skillet. Turn until the skin is blackened and blistered all over (about 6–10 minutes). Transfer to a bowl and cover to steam for 10 minutes — the steam helps the skin loosen so you can peel it off easily. Charring adds deep smoky notes that balance the sweet tomato jam.

Peel and dice the pepper: Once cool enough to handle, peel away the charred skin, remove seeds and stem, then roughly chop. Discard the skin and seeds. If you prefer more texture, slice thinly instead of chopping.

Make the tomato-garlic jam (tomato confit): Meanwhile, thinly slice one onion (about 150 g). Heat 2 tbsp olive oil and 1 tbsp butter in a medium skillet over medium-low heat. Add the sliced onion and 2 thinly sliced garlic cloves, a pinch of salt, and sweat gently for 8–10 minutes until translucent and sweet but not browned. Add the chopped tomatoes, 1 tsp smoked paprika, 1/2 tsp salt (or to taste), and cook at a gentle simmer, stirring occasionally, until the tomatoes break down and become jammy — about 18–22 minutes. Cooking low and slow concentrates flavor and softens acidity, converting fresh tomato into a glossy, savory jam.

Finish the jam: When the tomato mixture is thick and reduced, stir in the chopped charred pepper and cook 2–3 more minutes to marry flavors. Taste and adjust seasoning with salt and black pepper. A glossy jam binds the dish and provides an acidic-sweet counterpoint to the starchy potatoes.

Crisp the second onion and garlic: While the jam finishes and potatoes are nearly done, thinly slice the remaining onion and 2 garlic cloves. Heat a small skillet over medium-high heat with 1 tbsp olive oil. Add the sliced onion in a single layer and let it color without moving for 2–3 minutes to develop caramelization, then toss for another 3–4 minutes until deeply golden. Add the sliced garlic for the final 60 seconds to flavor the oil — garlic browns fast so add it toward the end. These browned pieces add texture and toasty umami.

Combine and plate: Remove the potatoes from the oven and transfer to the skillet with the caramelized onion and garlic (or toss together in a large bowl). Give a quick toss to coat: the hot potatoes will pick up the flavored oil and onion, adding savory depth. Spread a generous spoonful of the tomato-garlic jam on each plate and mound the potatoes on top (or serve jam on top for a more integrated bite). Finish with a drizzle of olive oil and a sprinkle of flaky sea salt if using. The contrast of textures (crispy potato, jammy tomato, tender charred pepper) is what makes this dish special.

Serve: Serve hot as a vegetarian main with a simple green salad, or as an impressive side to grilled fish or roasted meat. Leftovers keep 2–3 days refrigerated; re-crisp potatoes in a hot skillet or oven to refresh the texture.