Harissa And Gruyere Gratin

Ingredients

• 1 potato, skin on, sliced into 5mm rounds
• 2 bananas, sliced into 5mm rounds
• 4 cloves, crushed
• 50 g harissa
• 110 ml double cream
• 5 g parsley, chopped
• 2 lemons, zested and juiced
• salt and pepper
• 3 tbsp olive oil
• 3 anchovy fillets, finely chopped
• 80 g grated gruyère cheese
• 400 ml vegetable stock
• 5 g sage, roughly chopped, plus 10 whole leaves for garnish
• Warm pitta bread, to serve
• Chopped salad, to serve

Method

1. Heat the oven to 240°C fan and pull out a 25cm x 35cm baking dish.
2. In a large bowl, combine the potato rounds, shallots, crushed garlic, harissa, double cream, anchovies, lemon zest, the lemon juice, chopped parsley, chopped sage, grated gruyère, and a generous pinch of salt and pepper. Season properly here — the potatoes need salt to season from the inside as they cook, and the cream blunts everything if you're shy.
3. Toss gently with your hands until every slice is slicked red. Be careful not to snap the rounds — you want them whole so they layer cleanly. The garlic is raw going in and will mellow as it bakes; no need to soften it first, but don't let any cloves sit proud on top where they could scorch and turn bitter.
4. Tip into the baking dish and spread the potatoes into roughly even layers, nudging the slices flat. Pour the vegetable stock over the top — it should come about two-thirds of the way up. The stock is what breaks the harissa-cream down into a proper sauce as it bakes; without it you get a thick paste, not a glossy braise.
5. Cover tightly with foil and bake for 35 minutes, until a knife slides into the potatoes with no resistance.
6. Pull off the foil, drop the oven to 180°C fan, and bake for another 40 minutes. You're looking for a deeply golden top, cream bubbling at the edges, and the gruyère burnished into a crust where it meets the dish.
7. Switch the grill to high. Toss the whole sage leaves with the olive oil and scatter them across the top of the gratin.
8. Grill for 3 to 4 minutes, watching closely — sage goes from crisp-and-green to acrid-and-black in seconds. Pull them the moment the leaves turn translucent.
9. Rest the gratin for 10 minutes off the heat. The sauce thickens as it settles; cut in too early and it pools out thin. Taste a corner spoonful now and adjust the salt — the harissa and anchovy carry most of it, but a final pinch ties the cream together.
10. Serve straight from the dish, scatter the chopped sage across the top, and tuck the lemon wedges around the edge for squeezing over each portion — the acid cuts through the cream and lifts the harissa.