Step 1

Heat the oven to 180ºC fan/gas Put the loaf on a sheet of baking paper/foil and cut at 2cm intervals three quarters of the way through so the slices all remain joined together at the bottom. Set aside.

Step 2

Put the peppers, anchovies and garlic in a roasting tin, drizzle with the olive oil and roast for 25 minutes until the peppers are soft and lightly charred. Set the peppers aside and keep the tin handy.

Step 3

For the spinach butter: beat the butter with an electric mixer, then beat in the spinach, lemon zest and juice, parsley, and the anchovies and garlic from the roasting tin (reserve the oil). Beat in some black pepper and a little salt to taste

Step 4

Spread the spinach butter between the slices of bread, then add the peppers (peel first if you prefer), mozzarella, tomatoes and the spinach and basil leaves. Drizzle the oil from the tin over the top (and any extra butter, if you like), then wrap in baking paper and foil and bake for 30-35 minutes. Serve straightaway or keep wrapped to take on your picnic.