Step 1: The Aeration Phase

1. In a stand mixer or using a hand mixer, beat the **shortening** and **powdered sugar** on medium-high speed.
2. Continue for 3–5 minutes until the mixture looks pale, fluffy, and resembles whipped cream. This is where you build the biscuit’s internal structure.

Step 2: Incorporating the Liquids

1. Add the **eggs** one at a time, beating well after each addition.
2. Mix in the **vanilla extract**. The mixture might look slightly curdled at this stage; this is normal and will smooth out once the dry ingredients are added.

Step 3: Folding the Flour

1. Add the **flour, cornstarch, salt, and baking powder**.
2. The Golden Rule: Mix on the lowest speed only until the flour streaks disappear. If you overmix, you will develop gluten, and your biscuits will be “tough” or “stringy” instead of melting.
3. The Rest: Wrap the dough and refrigerate for 15 minutes. This allows the starch to hydrate and the fat to firm up.

Step 4: The Dual-Tone Shaping

1. Divide the dough into two equal parts.
2. **Vanilla Portion:** Roll into small balls (about the size of a walnut) and flatten slightly on a baking sheet.
3. **Chocolate Portion:** Fold in the **cocoa powder** gently. Roll into identical-sized balls.
4. Bake at **180°C (350°F)** for 15-20 minutes. The vanilla biscuits should be set but not browned; they should remain pale.

Step 5: The Final Assembly

1. Once cooled, spread a small amount of **jam** on the flat side of one biscuit.
2. Press a second biscuit on top. Roll the edges in **shredded coconut** so it sticks to the exposed jam.
3. Drizzle with **melted chocolate** for a professional finish.