In a food processor or bowl with an electric whisk, briefly blend the ricotta and salt (just to combine them). Then, with the motor running, slowly drizzle in the oil, processing until the ricotta is smooth and creamy, about 2 minutes. Fold in the chopped basil and chives.
Toss the nasturtium leaves or rocket in the olive oil and a pinch of salt.
Spread the ricotta over the base