Lemon Curd:

1. In a small pot bring 2/3 Cup sugar, 1/8 tsp salt, zest of 2 lemons, 1/2 Cup lemon juice and 6 Tbs. butter just to a boil.
2. While you are watching for that to boil, soften the unflavored gelatin in the cold water.
3. Add the soften gelatin to the boiling contents of the pot and whisk until dissolved.
4. Crack the 2 eggs into a small deep bowl or a 4 cup measuring cup. 
5. Whisk them well.
6.  Slowly drizzle the hot liquid into the eggs while whisking vigorously to temper the eggs. 
7. After you've whisked all the hot liquid into the eggs pour it back into the pot and place it back on the stove over medium heat.
8. Continue to whisk until the lemon curd thickens enough to coat the back of a spoon.
9. Remove from the heat.
10. It's best if the lemon curd is not super hot when it's used in this cheesecake. To cool it down quickly put the pot over a container filled with ice.  Whisk it here and there as you continue to work on the rest of the cheesecake.

Shortbread Crust:

1. Crush the shortbread cookies into fine crumbs and incorporate the sugar and butter into them.
2. Press into a 9 inch springform pan.

Filling:

1. Preheat your oven to 325 degrees.
2. In a large mixing bowl, beat the cream cheese until smooth.
3. Beat in the 2/3 Cup sour cream and 3/4 Cup lemon curd until smooth.
4. Beat in 2/3 Cup sugar.  This is the time to make sure your mixture is completely smooth.  No cream cheese lumps.
5. Add 2 tsp vanilla and 3 Tbs. flour.  Beat until smooth.
6. Add the mix and only beat until the 3 eggs are incorporated.  
7. Pour over the crust in the springform pan.
8. Spoon 1/2 cup lemon curd into 3 or 4 strips across the top of the filling.
9. Move a knife in figure 8 type motions through the lemon curd and cheesecake filling to swirl it.
10. Bake at 325 degrees for 50-60 minutes.  The center 2-3 inches should still be jiggly.
11. Cool the cheesecake to room temperature then place it in the fridge overnight to cool and chill completely.
12. Run a sharp knife around the edge of the cheesecake and remove the outer ring of the spring form pan.
13. Slice your cheesecake and serve.