Heat your oven to 200°C/Fan 180°C/Gas 6. Place a couple of flat baking trays in the oven to heat up.
Tip the flour into a bowl, reserving 1 tbsp for later. Add 1 tsp baking powder. Whisk 1 tbsp ricotta with 2 tbsp cold water and a pinch of salt. Tip into the flour and mix. Knead in the bowl to form a smooth dough, adding 1 tsp water at a time if needed. Cover and set aside to rest.
Tip the remaining ricotta into a bowl. Zest and juice the lemon. Finely chop the parsley stalks. Finely chop the chilli, flicking out the seeds. Add half the lemon zest and juice, half the chilli and all the parsley stalks to the ricotta. Add plenty of seasoning. Whisk well.
Trim the leeks. Cut the leeks in half lengthways and give them a good rinse to remove any dirt. Slice as finely as possible. Roughly chop the parsley leaves. Set aside.
Heat 1 tbsp oil in a large frying pan over a medium heat. Gently fry the leeks for 5 mins till just softened. Add the remaining lemon juice to the pan and season well. Take off the heat and set aside.
Dust your worksurface with half the reserved flour. Roll half the dough into a large oval. Repeat with the remaining dough and flour. Pop the dough bases on the heated baking trays and slide back into the oven. Bake for 5 mins till the bases are crisp and have a few bubbles.
Spread the ricotta mix over the bases. Top with the leeks. Scatter over the flaked almonds. Pop back in the oven for 10 mins.
Meanwhile, heat ½ tbsp oil in a clean frying pan. Add the remaining lemon zest and chilli. Fry for 2-3 mins till crisp. Remove the pizzettes from the oven and drizzle over the chilli and lemon oil. Scatter over the parsley leaves and a little rocket to serve.