Step 1

Preheat oven to 350°F. Line an 8x8 glass baking pan with parchment paper.

Step 2

In a medium bowl, blend together butter and 1/4 cup sugar. Add in flour and salt, beating until well combined.

Step 3

Press into the bottom of prepared baking pan. Bake for 20 minutes, or until firm and golden brown.

Step 4

In another bowl, whisk together the remaining 1 1/2 cups sugar and 1/3 cup flour. Whisk in the eggs, lemon juice, lemon zest and vanilla extract. Pour over the baked crust.

Step 5

Return to oven and bake for 20 to 25 minutes, or until top is light golden brown.

Step 6

Let cool completely, or refrigerate for 2 hours to chill, before slicing into squares.

Step 7

Dust with powdered sugar before serving.