Crack the eggs into a large mixing bowl.
Pour in the oil.
Add the sugar and beat with a hand mixer on high speed for 10 minutes.
Next, add the cottage cheese (farmer cheese).
Add the flour mixed with the baking powder, then beat again on the lowest mixer speed until just combined.
From the 3 apples, dice 1 apple into small cubes. Add the apple cubes to the bowl and fold to combine.
Grease the baking pan with butter or line it with parchment paper, then pour the batter into the pan and spread it out in an even layer.
Preheat the oven to 350°F (180°C). Slice the remaining 2 apples into long wedges and arrange them over the top of the batter. Bake for 40 minutes.
After 25 minutes of baking, cover the pan loosely with aluminum foil and continue baking until the top is lightly golden and the center is set.
Dust with powdered sugar if you like, then slice and serve.