Blend basil leaves with 2 tablespoons of olive oil, parmesan cheese, pine kernels, a little salt and pepper to obtain a smooth pesto sauce. Set aside.
Blend whole wheat crackers to get a coarse flour, add melted shortening and stir to obtain an homogeneous mixture. Divide it in shot glasses or an 8 inch round mold and put in the fridge.
Heat 5 tablespoons of cream in a small pan, add the agar agar and mix well. Bring to the boil and simmer on low heat for 3 minutes, stirring constantly.
Mix the ricotta cheese with pesto sauce, add the agar agar cream mixture and mix well using a whisk. Whip the remaining cream and add it to the ricotta pesto cheesecake filling using a spatula, stirring gently from bottom to top.
Pour the cheesecake filling over the cracker crust then put in the fridge for 2 hours.
Top the cheesecake with cut tomatoes seasoned with oil, salt and pepper, sprinkle with sesame seeds or roasted pine kernels and serve.