How to make the Lemon Souffle:

1. Preheat the oven to 375 degrees F and position a rack in the center.
2. Lightly butter the bottoms and sides of 8 (6-ounce ramekins). Dust these with sugar and knock out the excess over the sink.
3. In a medium saucepan, combine egg yolks, milk, lemon zest, lemon juice, 1/2 c. sugar and cornstarch. Whisk until smooth, and place saucepan over medium heat, cook for about 8 minutes or until the pastry cream is thick and viscous like pudding. Make sure to continue stirring constantly, especially when it starts to feel a little thick to prevent burning. Do not overcook though or the cream will split.
4. Remove from heat and whisk in butter, vanilla, and salt.
5. Transfer the pastry cream to a large bowl and set aside.
6. In the bowl of a standard mixture, fitted with a whisk attachment (or you can use a hand mixer), add egg whites and cream of tartar.
7. Beat on medium speed for one minute. Sprinkle remaining 1/4 c of the sugar and continue to beat until the egg whites form stiff peaks. You know they are the right consistency when you hold the whisk up and the egg whites on the end stand straight up and don't sag at all. But do not over beat or it will just look clumpy.
8. Using a silicone spatula, gently fold 1/3 of the egg whites into the lemon souffle base. When this is mostly incorporated, add remaining egg whites, in two additions, until combined and there are no white streaks. Make sure not to hit the side of the bowl with whatever you are using to mix the egg whites into the base with because this will ruin the air bubbles you have worked so hard to incorporate up to this point. NO BANGING!!!
9. Evenly divide the mixture between the prepared ramekins. Run your finger around the inside edges (at the top) of each ramekin to wipe away any stray mixture (this will help ensure an even rise) and place the souffles CAREFULLY on a baking sheet and transfer into the oven.
10. Bake for 18-20 minutes or until the souffles are puffed and golden and the center is just set. Test doneness by GENTLY shaking the baking sheet. The souffle should jiggle only slightly. If centers are too soft, quickly close the oven and bake an additional 2 to 3 minutes.
11. Serve immediately with strawberry sauce!

Strawberry Sauce

1. Place the strawberries, sugar, lemon juice and cornstarch into a medium saucepan, stir to combine and place over medium heat.
2. Bring to a boil and reduce heat to simmer, cook just until sugar dissolves and sauce starts to thicken, about 5 minutes.
3. Taste and adjust with additional sugar and lemon juice as needed until the taste is how you like it. You can also put this mixture into a food processor if you want it very smooth.
4. Chill until needed.