These savory cheese tarts owed its origin to Dutch's Kaasstangels (Cheese Sticks) are popular cookies for festive occasions like Chinese New Year, Christmas, and Eid Al Fitr in Indonesia.
Place the butter at room temperature for 30 minutes to soften. If it's warm where you are, it may not take that long. Place the butter and egg yolk in a stand mixer bowl with a flat beater attached. Whip the butter and egg until just combined. Do not overbeat the butter or the kastengel crumbles easily after being baked. Alternatively, you can just mix the butter by hands using a spatula
Once the butter and egg are combined, add the flour, milk powder, cheese, and salt. Use your hand to mix everything into a dough. It may seem really dry at first, but keep mixing and they will come together into a dough
Chill the dough:
Wrap the dough and chill it in the refrigerator for another 30 minutes
Shape the dough:
Preheat oven to 300 F (150 C) for a conventional oven. For a convection oven, please lower the temperature by 20 degrees. Line baking sheet with parchment paper. Place a parchment paper or silicon mat on a working surface. Roll the dough out into a rectangle about 1/4-inch thickness. Use a knife or pizza cutter to cut the dough about 1/2-inch in width and then cut into individual about 2-3 inches long. You will probably get about 40-45 pieces
Bake:
Arrange them on the baking sheet. Brush with egg wash and sprinkle with more cheese. Bake for 35 minutes or until golden brown. This really depends on your oven too, you may need a bit longer time or shorter
Let the kastengel cool off on the baking sheet for 1 minute and then remove to cooling rack to let them cool down completely before storing
Storage:
Store in an air-tight container and they can last up to one month
Video
Notes
If you don't have cake flour, simply use 175 gr all-purpose flour + 25 gr cornstarch to make your own cake flour.