Baked Tomato, Gruyère and Potato Gratin

• butter↗кілька шматочків

  plus extra for greasing

• thyme sprigs↗4-5
• Gruyère↗200g g

  grated

• Parmesan↗100g g

  (or vegetarian alternative), finely grated

• heavy cream500ml ml
• vegetable or chicken broth300ml ml
• large potatoes1 ½kg kg

  thinly sliced (with mandoline if available)

• round shallots8

  or 4 banana shallots, thinly sliced

• fat garlic cloves↗3

  finely chopped

• walnuts↗100g g

  chopped

• mixed tomatoes650g g

  chopped

• breadcrumbs↗5 ст. л. tbsp

Step-by-step instructions

1. 1

   Preheat the oven to 180 °C (160 °C with convection, gas 4). Generously grease a large deep oven‑proof dish. Remove the leaves from three thyme sprigs. In a large bowl combine the grated Gruyère with all ingredients except 2 tbsp of grated Parmesan, then whisk the cream with the broth.

2. 2

   Begin layering the thinly sliced potatoes, sprinkling them with shallots, garlic, thyme leaves, some Gruyère, chopped walnuts, and generously seasoning with salt and pepper. Drizzle a little of the cream mixture over each layer. When you have used half of the potatoes, add half of the sliced tomatoes. Continue layering the remaining ingredients, finishing with a final layer of potatoes. Top with the remaining tomatoes, sprinkle breadcrumbs, the remaining Parmesan and walnuts, and thyme leaves for garnish. Add a few pieces of butter, cover the dish with foil.

3. 3

   Bake for 1 hour 15 minutes, then remove the foil and bake for another 40 minutes until the top is golden and crisp and a knife inserted into the centre slides in easily. Let the gratin rest for 10‑15 minutes before serving.