Step 1

For the tomato relish, heat oil in a frypan over medium heat. Add the eschalot and mustard seeds, and cook, stirring occasionally, for 3-4 minutes, until soft. Add tomatoes, sugar and vinegar, and cook, stirring occasionally, for 5 minutes or until tomatoes are soft. Cool, then season to taste with black pepper.

Step 2

Cook the potatoes in a large pan of boiling salted water for 15 minutes or until tender. Drain well, return to the pan and roughly mash. Meanwhile, place cabbage in a colander in the sink and pour over 2 cups (500ml) boiling water. Rinse under cool water, then squeeze out excess. Add cabbage, onion, milk and 20g butter to potatoes and mix until well combined. Season to taste, then stir in the grated cheese.

Step 3

Preheat grill to high. Heat remaining butter and oil in a non-stick frypan over medium-low heat. Add bubble and squeak mixture, spread evenly over base. Reduce heat to low and cook for 12-15 minutes or until base is crisp. Place under the grill and cook for 2-3 minutes or until the top is golden. Stand in the pan for 5 minutes, then invert onto a board, cut into wedges and serve with relish and baby spinach.