Thumbprint Cookies with Lemon Jam

What you will need:
2 sticks butter
2/3 cup sugar
½ tsp salt
2 ¼ cup all-purpose flour
2 tbsp lemon zest, grated
1/3 cup lemon jam
2 tbsp sprinkles

Steps to yummy goodness:
1) Preheat oven to 175C.
2) Mix butter, sugar, salt and lemon zest until smooth.
3) Add in flour and mix with a spatula until combined well.
4) Cover and chill it for 30 minutes.
5) Line cookie sheets with baking paper.
6) Make 1 inch balls from dough and place them on baking paper leaving enough space between each.
7) Press on each cookie with your thumb to make dents.
8) Place 1/3 tsp lemon jam in these dents.
9) Bake them for 20 minutes.
10) Add sprinkles on each when they are still warm and cool them on a wire rack.