Take the cold risotto out of the fridge and break up any large clumps with a fork in a mixing bowl. Stir in 1 tablespoon of the Parmesan and taste, adding a pinch of salt if it tastes flat.

Heat 1 tablespoon of the butter and the olive oil in a 20 cm / 8-inch nonstick skillet over medium heat until the butter foams.

Tip in half the risotto, about 250 g, and press it firmly and evenly across the base of the pan with the back of a spoon, forming a disc about 1.5 cm thick.

Cook undisturbed for 5 to 6 minutes, until the underside is deep golden and the edges look dry and pull slightly from the pan.

Slide the cake onto a large flat plate. Place the skillet upside down over the plate, then flip both together so the cake drops back into the pan uncooked-side down.

Add a small knob of the remaining butter around the edges and cook the second side for 4 to 5 minutes, until equally golden and the center feels hot when pressed (165 F / 74 C in the middle).

Slide the cake onto a board, sprinkle with a little more Parmesan, and cut into wedges. Repeat steps 2 to 6 with the remaining risotto to make the second cake.

Scatter with chives or parsley just before serving.