Combine the allulose, stevia glycerite, lemon juice, lemon collagen, and eggs in a heavy medium-sized saucepan and whisk to blend. Add the butter and salt. Place over medium heat and cook, whisking constantly, for about 12 minutes, or until the mixture thickens and coats the back of a spoon thickly (do not boil).
3/4 cup powdered allulose, 1/2 cup lemon juice, 1 scoop Further Food Lemon Collagen, 4 large eggs, 1/2 cup unsalted butter, 1/4 teaspoon Redmond Real salt