In a medium-sized bowl, using an electric mixer, beat together softened butter, sugar and egg. Mix until creamy.
In a small bowl, sift together flour, baking powder and salt.
Slowly add dry ingredients into wet ingredients (one third at a time), and mix in-between.
Once your cookie dough has taken form, roll into a large ball and cover it with plastic wrap. Refrigerate for 30 minutes.
Remove cookie dough from the refrigerator. Preheat the oven to 350 degrees F and line a baking sheet with parchment paper.
Roll dough into balls, about 1.5 inches in-size. Place gently on a baking sheet, about 2 inches apart.
Use a ½ teaspoon measuring spoon to form a dent in the middle of each cookie.
Bake for 8 minutes and remove from the oven. Create a deeper indent if necessary.
Spoon a little bit of jam into each indent and return to the oven to bake for another 2-3 minutes. Cool on a wire rack.
In a small bowl, mix together icing sugar and water. Drizzle over the top of the cookie - allow it to sit for a few minutes. Serve and enjoy.