Preheat oven to 350 degrees Fahrenheit. Grease a 9x9 pan and set aside.
Mix gingersnap cookie crumbs, brown sugar, flour, and salt. The pour in melted butter and mix until thoroughly combined.
Pour mixture into pan and press crumbs into pan. Make sure the crust is evenly dispersed and that the crust is pressed firmly into the pan. I like to use the back of my measuring spoon to press the crust into the pan.
Bake crust for 10 minutes. Let cool before adding the lemon curd mixture.
Lemon Curd:
Whisk together eggs and sugar until smooth. Then whisk in lemon juice and zest.
Slowly add in flour and whisk together until smooth and thoroughly combined.
Pour lemon curd mixture over the cooled gingersnap crust and bake for 32-36 minutes until the curd is set but still jiggles a little in the middle. Cool completely. Dust generously with powdered sugar and slice and serve.