Place the ricotta, olive oil, and salt in a food processor. Blend until smooth and light. Place aside.
Place all the dressing ingredients (except olive oil) in a food processor and pulse. While it is running drizzle in the olive oil until the dressing is incorporated.
Toss the arugula and tomatoes with the dressing.
Spread the whipped ricotta onto a platter then top with the rest of the salad.