Add white chocolate, eggs, lemon zest, lemon extract, vanilla and salt to a blender. Pulse until chocolate is broken into bits.
In a small bowl, heat cream in the microwave in 20 second increments until just steaming (do not boil).
With the blender running, slowly pour the hot cream into the chocolate mixture. Continue to blend until completely smooth.
Divide custard evenly amongst 3 ramekins or custard cups.
Pour 1 cup of water in the Instant Pot and insert the steam rack.
Using the display panel select the MANUAL or PRESSURE function*. Use the +/- keys and program the Instant Pot for 0 minutes.
When the time is up, let the pressure naturally release for 5 minutes, then quick-release the remaining pressure.
Carefully remove the ramekins from the pot to a cooling rack. When completely cool, cover with plastic wrap and refrigerate for at least 4 hours.
Meanwhile, combine raspberries, 2 tbsp water and sugar in a blender. Blend until smooth, adding additional water as needed. Strain the sauce to remove seeds.
At least thirty minutes before serving, top each ramekin with 1-2 tbsp of sauce and refrigerate.
Recipe Notes
*The MANUAL and PRESSURE COOK buttons are interchangeable.