To begin, prepare the wafer batter. In a large mixing bowl, combine the flour, corn starch, sugar, and salt. Slowly add the milk, melted butter, and vanilla extract while whisking continuously to form a smooth, lump free batter. Allow the batter to rest for 15 minutes to ensure a uniform texture and to let the flour fully hydrate.

Preheat a non-stick wafer or crepe maker to medium heat. Lightly grease the surface with a small amount of oil or butter. If you don’t have a wafer maker, a flat non-stick skillet can be used. Ensure it is heated evenly to achieve thin, crispy wafers.

Pour a small ladleful of batter onto the heated surface, about 2–3 tablespoons, and quickly spread it into a thin, even layer using the back of the ladle or a spatula. Aim for a circular shape around 15–20 cm in diameter. Cook for 1–2 minutes on one side until the edges are golden.

Flip the wafer carefully using a spatula and cook for an additional 1–2 minutes until both sides are golden and crisp. Transfer the finished wafer to a wire rack to cool completely. Repeat the process with the remaining batter, ensuring the pan is lightly greased between wafers if needed.

While the wafers cool, prepare the fillings. Arrange the dulce de leche, grated cheese, fruit preserves, and shredded coconut in small bowls for easy assembly. If using guava jam, slightly warm it to make it easier to spread.

Take one wafer and spread a generous layer of dulce de leche over its surface. For an authentic Colombian twist, sprinkle a small amount of grated cheese or coconut on top. If you prefer a fruitier flavour, spread a thin layer of fruit preserves before adding other toppings.

Place a second wafer on top of the filling to create a sandwich like structure. Gently press the edges to seal the filling and ensure an even distribution without cracking the wafer. Repeat the process for all wafers.

Serve the obleas on a large platter or individually on small plates. Garnish with a light dusting of powdered sugar or a drizzle of additional dulce de leche for an elegant touch. Pair with a cup of Colombian coffee or hot chocolate for an authentic dining experience. For storage, keep the obleas in an airtight container to maintain their crispness.