Return the butter and condensed milk to room temperature. Combine the cake flour, corn starch, and baking powder, and sift.
Knead the butter into a cream-like state, add in the condensed milk, and mix well.
Add in the skim milk and sifted powder, roughly mix with a spatula, add in the tea leaves (minced when not using from a tea bag) as well, and stir together evenly.
Flatten it out and wrap in plastic wrap, then let it sit in the fridge for more than 30 minutes.
Preheat the oven to 170°C. Divide the dough into 25 pieces after taking it out of the fridge.
Ball up each piece, and spread out on a cookie sheet covered with cooking paper with spaces inbetween.
Lightly coat the bottom of a flat-bottomed glass with flour (bread or cake flour not listed in the ingredients), and squish each piece into about 3mm thick.
Poke holes into them with a fork etc.
Bake in the preheated oven for about 10~12 minutes.
After baking, let them cool on a cake rack etc.
Story Behind this Recipe
In order to make snacks that were gentle on the body and the wallet, I am always thinking of snacks that use small amounts of butter, eggs, and sugar (or don't use at all).
You can use potato starch flour in place of the corn starch. When molding in steps 5~7, roll out the dough to about 3 mm thick with a rolling pin, and cut out with a cookie cutter if you like. I don't mind, but cutting it with a cup and serrating the edges will give it a simple appearance and will bring out the delicious crunchiness; it is also more fun to squeeze the edges, so I recommend making it with your kids.