Preheat oven to 325 and place rack in center of oven.

Line an 8x8 glass baking dish with parchment paper.

Use a paper towel to spread a thin layer of soft butter on paper.

Using a hand mixer or bowl mixer, mix butter and sugars in a large bowl until well blended.

Add salt, lemon juice and lemon zest and mix till well incorporated.

Add flour and mix. At first the dough will crumble and fall apart.

Remove dough from bowl and set on a cutting board or counter and gently knead with hands until dough forms a ball.

Place dough in prepared 8x8 baking dish and press till dough is evenly distributed in the pan from edge to edge. Dough will only be about ¼ inch thick.

Sprinkle dough with granulated sugar and bake for 25- 30 minutes or until dough is cooked and slightly golden.

Remove from oven and let cool for 10-15 minutes. Cut into bar shapes while still slightly warm. Gently remove first bar with a knife and then use a spatula to remove the rest. Place on a rack to cool.

Use a fork to blend lemon curd and mascarpone.

Very gently spread mascarpone mixture on each lemon bar.

Place berries on top.

Using a screen colander dust cookies with powdered sugar.

Then sprinkle with lemon zest! Yum!