Preheat the oven to 350 degrees F and line a baking sheet with parchment paper. Soften Butter to room temperature and place it in a large mixing bowl. Add 175 grams of All-Purpose Flour (roughly 1⅓ cups plus 2 tablespoons).

Mix Butter and Flour together with a pastry blender. The mixture should form into coarse crumbs. It should hold together when squeezed, and easily break apart with a bit of pressure.

Add ¼ cup (60ml) of Sweetened Condensed Milk to the butter mixture.

Use a large spoon to mix it until thoroughly combined.

As the mixture begins to form into a dough, use your hands to knead it into a ball. If the cookie dough is too sticky then mix in another 1-2 tablespoons of All-Purpose Flour. Alternatively, if the dough is a little dry then add a drop or two of Sweetened Condensed Milk.

Sprinkle the counter with a light dusting of Flour, place the cookie dough on the counter, and use your fingers to smooth out the dough until it is fairly flat.

Then use a rolling pin to roll the dough until it is roughly ¼-inch thick.

Cut 2-inch circles out of the dough using a circular cookie cutter. After cutting all the circles that you can from the cookie dough, gather the remaining dough and press it back together, then flatten it out again, and cut out as many more cookies as you can. There should be enough cookie dough to make about 26 cookies.

Cut out a smaller hole in the middle of half of the cookies. A piping tip works really well for cutting out the center circles.

Place the cookies on the prepared baking sheet. You can place the cookies quite close together as they will not spread very much. Bake the cookies in a preheated oven at 350 degrees F for 7-9 minutes. Remove the cookies from the oven and allow them to fully cool on the baking tray.

Take a cooled cookie that does not have a hole in it and place a dollop of Nutella in the center.

Then take a cooled cookie that has a hole in it and place this on top to make a sandwich cookie. Serve and enjoy!