Cut the halloumi into 8 slices. Mix together the lemon zest, juice and 2tbsp of cold pressed rapeseed oil. Add the cheese and marinate for 5 minutes.
Meanwhile, cut the bread in half and each in half again lengthways. Brush each side with the remaining rapeseed oil and griddle for 1-1½ minutes each side until golden and crisp. Griddle the cheese for 1 minute on each side until golden. Top the bread with the peppers and then the cheese. Drizzle over the remaining lemon mixture.
Serve with a green salad and halved boiled eggs for a larger lunch.
This sandwich is very indulgent, so shouldn't be eaten too often. But it's great for those special occasions!