Place the water into the inner pot and place the steam rack inside. You will need six 6-ounce (175ml) ceramic ramekins for this recipe.
Place the cream and half of the sugar into a small saucepan and heat over low heat. Stir occasionally. Meanwhile, in a medium bowl, place the egg yolks, lemon zest, lemon juice, cornstarch, and remaining sugar and whisk well. When you see small bubbles in the cream mixture, after about 4 to 5 minutes, remove from the heat and pour a little into the bowl with the egg yolk mixture. Whisk well. Add half of the remaining cream mixture and whisk. Add the remaining cream mixture and whisk in. Add the yogurt or labne and whisk well. Strain into another bowl and press as much liquid as possible through the sieve.
Divide the batter among the ramekins, about 1/2 cup (118ml) of the batter in each. Cover each ramekin with a small piece of aluminum foil. Place 3 ramekins onto the steam rack and then stack the other three on top.
Secure the lid ensuring that the steam release handle is in the Sealing position. Press the Pressure Cook button and set the cooking time for 7 minutes. When the cooking time is complete, let the pot sit to naturally release the pressure, for about 15 minutes. Turn the steam release handle to the Venting position to release any remaining pressure. Remove the lid. Carefully remove the ramekins to the counter and let cool for 30 minutes. Refrigerate for at least 4 hours or overnight, until firm.