Lightly coat 4 (4 ounce) ramekins with cooking spray.
In a large bowl, whisk together ricotta, egg yolks, 1 TBSP of sugar substitute, lemon zest, lemon extract and vanilla extracts.
In another small bowl with an electric mixer at high speed, beat egg whites until soft peaks form; approximately 2-3 minutes. Gradually add remaining 2 TBSP sugar substitute and continue to beat until stiff peaks form.
Gently fold egg whites into ricotta mixture; just until combined.
Spoon ricotta mixture into ramekins. Bake until souffles have risen, are set and lightly browned; approximately 15 minutes.