Preheat the oven to 400°F (200°C), with the oven rack in the middle position and the baking sheet lined with parchment paper.

Cream together ¾ cups of sugar and ½ cup of softened butter until smooth and fluffy, then add in 1 tsp of vanilla extract.

Beat in 1 egg until fully combined and smooth.

Gradually add in 1 ¾ cups of flour, ½ tsp of baking powder, ½ tsp of baking soda, and ½ tsp of salt, mixing until a smooth dough forms.

Incorporate green gel food coloring until uniformly mixed throughout the dough.

Scoop out portions of dough, roll into balls, and space 2 inches apart on the baking sheet.

Gently press down each ball with a fork to create an indentation resembling a turtle shell.

Roll smaller balls for the turtle heads and feet, attaching them to the body with a dab of water.

Bake for 5-7 minutes, until the bottoms are lightly browned.

Let cool on a wire rack for about 5 minutes, then use an edible marker to decorate the eyes.