Step 1

Whisk together lemon juice, eggs, egg yolk, and granulated sugar in a small saucepan.

Step 2

Place pan over medium-low heat. Whisking continuously, cook mixture until it reaches 180 degrees F. Mixture will start to thicken.

Step 3

Remove from heat and stir for 1-2 minutes to bring down temperature. Stir in lemon zest.

Step 4

Pour mixture into a blender or food processor. Blend and slowly add butter one tablespoon at a time until fully combined.

Step 5

Pour filling into the premade crust and refrigerate for 2-3 hours before serving.

Step 6

Serve with vanilla ice cream or whipped cream.