Zucchini and Ribbon Pasta Gratin

For the pasta:

sift the sorghum flour, tapioca starch, xanthan gum and salt into a bowl and whisk to combine.

Slowly add the warm water and olive oil, using an electric whisk. Continue mixing for about 2 minutes, to a firm but not sticky dough. If it is too dry, add more water. If it is sticky, add a little more tapioca starch. Cover the dough with cling film and chill for 30 minutes.

Take a tennis ball-sized piece of dough and squash it flat. Keep the remaining dough covered with cling film, to prevent it from drying out.

Push the piece of dough through the pasta roller on the widest setting. The dough will crumble as it comes out of the pasta machine. Patch the pieces together gently and push through again on the widest setting. Repeat until the dough comes out in one piece.

Fold the sheet into 3 pieces and roll through the widest setting. Repeat 3 times until you have a rough square shape, then start working it through the machine, taking it down one setting at a time, until the thinnest setting. This will produce a long, wide sheet of pasta.

Repeat with the remaining dough.

You can also roll the dough by hand using a rolling pin but you'll need to roll the pasta sheets really thinly.

Using a sharp knife cut the dough into thin strips and set aside to dry.

For the courgettes: heat the oven to 180°C (160° fan) 350°F gas 4. Grease a large baking dish.

Put the courgettes in the dish in a single layer.

Whisk together the lemon juice and olive oil, then drizzle over the courgettes. Turn to coat.

Bake for 20-30 minutes until just tender.

Drop the pasta strips into a large pan of boiling salted water and cook for 1 minute. Drain well.

For the sauce: put all ingredients except the cheese into a food processor and blend until smooth and creamy.

Layer the pasta, courgettes and sauce in the baking dish, as in the photo. Sprinkle with cheese, if using. Dot the courgettes with pesto.