Pommes Anna with chive oil and pickled mustard seeds

Layers with a fresh finish

Pommes Anna is all about potatoes, butter and carefully building the layers. Waxy potatoes hold their shape when thinly sliced; Nicola or Charlotte are good choices. A mandoline makes evenly thin slices, so they cook at the same time. Don’t rinse them after slicing: the starch on the surface helps bind the layers together. A heavy, ovenproof frying pan distributes the heat evenly and gives the cake a firm base.

Clarified butter is butter with the water and milk solids removed. This means it can handle higher heat than regular butter and helps the potatoes brown more evenly. You can buy clarified butter ready-made or make it yourself by gently melting butter and pouring off the clear fat from the solids. Use enough to coat the slices lightly, but don’t let them swim in it. Press the layers gently as you arrange them; a compact cake is easier to turn over and will cut into neat wedges.

The chive oil adds a gentle onion flavour and a green colour, while the pickled mustard seeds bring little tangy, mildly spicy bursts. Let the seeds cool in their liquid after cooking to keep them fresh. The oil doesn’t need to be strained, but pour it through a fine-mesh sieve if you want a smooth finish. No chives on hand? Use a small amount of parsley; the flavour will be less oniony. Apple cider vinegar can replace the white wine vinegar in the pickle.

Serve the wedges straight away, while the outside is still crisp and the middle is soft and layered. They go well with roast chicken, pan-fried fish or a green salad with a sharp vinaigrette. Spoon the oil and mustard seeds over the potatoes on the plate, so the crust doesn’t get unnecessarily damp. Leftovers can be covered and kept in the fridge, then reheated in a frying pan over medium heat; this makes the bottom firmer again than reheating them in the microwave. If preparing ahead, store the oil and potatoes separately.