Cut the onion into small cubes. Cut 1/2 avocado into cubes and put aside, drizzled with a little lemon juice. Puree the rest of the avocado with the ricotta and milk. Chop or squeeze the garlic and add the onions. Season to taste with salt, lemon and cayenne pepper.
Cut the basil into fine strips and fold in.
Roast pine nuts in a pan without oil. Then sprinkle these on the cream and serve with the potatoes.