Mix the batter – In a bowl, whisk flour, sugar, salt, and instant yeast. Slowly add warm milk, stirring until smooth. Add egg and vanilla. Mix again until lump-free.
Rest the batter – Cover with a towel and let it sit for 30 minutes so the yeast can do its job. Stir in baking powder just before cooking.
Heat the pan – Place a non-stick skillet on medium-low heat.
Cook the pancake – Pour the batter into the pan and let it spread naturally. Don’t stir. Small bubbles should form on top. Cover with a lid and cook 7–8 minutes until set and golden at the edges.
Add the filling – Turn off the heat. Spread butter over the hot pancake so it melts. Sprinkle chocolate and cheese evenly, then drizzle with condensed milk.
Fold and slice – Fold the pancake in half. Cut into wedges and serve warm.