1. Preheat the oven to 320°F or gas mark 3.
2. Heat the butter in a frying pan and when hot add the slices of potato, season with sea salt and freshly ground black pepper. Fry for five minutes turning occasionally until they have a little colour. Then remove from the pan and set aside.
3. Whisk the eggs in a large bowl, and stir in the grated zucchini, Dubliner cheese, scallions and season with sea salt and freshly ground black pepper.
4. Pour the egg mixture over the potatoes and using a spoon evenly distribute the ingredients around the pan. Allow to cook for three minutes so a base cooks on the bottom. Then transfer to the pre-heated oven for 10 minutes.
5. While the frittata is cooking, making the pesto. Place the fresh basil, extra virgin olive oil, almonds, garlic, sea salt, and parmesan in to a food processor. Blend until you have a rough paste.
6. Serve a slice of frittata with the pesto drizzled over the top. If you have any pesto left over you can keep it in a sterilised jar in your fridge for up to one month.