In an oven-safe glass container that fits in the Instant Pot (7 x 3 works well), whisk together 4 (204g) the eggs and egg yolks. Add the sweetener and mix well. Add the salt, lemon zest and juice. Mix until combined. Wrap the container very tight with aluminum foil.

Pour 1 cup (250ml) cold water in the Instant Pot. Place a trivet in the bottom. Carefully place the filled container on the trivet. Close lid and pressure cook at High Pressure for 3 minutes, then Natural Release for 10 minutes.

Create Instant Pot Lemon Curd: Open the lid carefully. Carefully take out the glass container. Discard the aluminum foil. When you first see the egg mixture, it will look like an egg custard. Give it a few quick whisk and watch magic happens.

Add in the unsalted butter, and whisk to emulsify. The lemon curd will thicken as it cools.

Chill in the fridge for at least 4 hours before serving.