- In the bowl of a mixer, beat the butter on medium speed until creamy. Reduce speed to lowest setting and gently add the confectioners’ sugar and baking powder. Continue mixing until everything is incorporated. 
- Add the flour, one cup at a time, and then the egg yolks, one at a time; continue beating for a minute. Pour in the water and continue mixing until the dough is smooth and can form a ball. Wrap the dough in plastic wrap and place it in the refrigerator. Let it cool until it hardens enough to be manageable, at least 1/2 hour (can refrigerate up to a couple of days). 
- When ready to bake, preheat the oven to 375 degrees and cover a baking sheet with parchment paper. 
- Place half the dough on a piece of lightly floured parchment paper, sprinkle some flour over it and then place another piece of parchment paper on top. Use a rolling pin to gently roll out the dough, to about 1/4-inch thick. Remove the top piece of parchment paper and cut out circles with a round, 3-inch cookie cutter. With a smaller cookie cutter, make a circular indention in the middle of each cookie, without cutting all the way through the dough (there should be about a 1/4-inch space between the indentation and the edge). Press the edges of each cookie with a fork, as if marking the edges of a pie. Repeat the process with the remaining dough and roll it out again, making as many cookies as possible. 
- Space the cookies at least 1/4-inch apart on a cookie sheet and bake for about 10 minutes, until they are fully cooked and the bottoms are lightly browned. Remove from the oven and let cool; repeat with the remaining cookies.