Step 1

Preheat oven to 375 degrees F. Line a cookie sheet with parchment paper.

Step 2

Beat together butter and sugar on medium-high speed until light and fluffy, about 2 to 3 minutes. Beat in egg yolks and vanilla extract.

Step 3

Add flour and salt and mix until incorporated and dough comes together in a ball. If desired, chill for 30 minutes.

Step 4

Form dough into 1-inch balls (make sure they’re perfectly round), and arrange on prepared cookie sheet. Use a 1/2 tsp. measure to create perfectly circular craters in the center.

Step 5

Bake cookies for 8 to 10 minutes.

Step 6

Remove cookie sheet from oven. If indentations look shallow, further define them again, and fill each with a bit of jam.

Step 7

Bake for an additional 3 to 4 minutes, or until jam melts slightly and edges of cookies are lightly golden.