Preheat oven to 350ºF. Prepare a baking sheet with parchment paper
In a large stand mixer or mixing bowl cream together butter and sugar until smooth. Add in eggs and lemon juice and mix.
To the butter mixture add flour 1/2- 1 cup at a time until well combined. Add in the baking powder and salt and mix.
The dough should be soft and not sticky. Roll the dough into balls or use a scoop to place them on the cookie sheet. Flatten the balls with a fork. Top with thin lemon slices dipped in sugar if desired.
Bake for 10-15 minutes until firm and golden on the edges.