Begin by washing the zucchinis thoroughly. Grate them into a large mixing bowl using a grater.
After grating, sprinkle a little salt over the zucchini and let it sit for about 5 minutes to release excess moisture.
Use a clean kitchen towel or cheesecloth to squeeze the grated zucchini, removing as much water as possible.
To the bowl with the grated zucchini, add the corn kernels, chopped jalapeño, crumbled feta, flour, eggs, baking powder, salt, and black pepper. Stir until well combined.
Heat a non-stick frying pan over medium heat. Add 1 tablespoon of olive oil.
Once the oil is hot, use a tablespoon or small scoop to drop spoonfuls of the fritter mixture into the skillet. Flatten them slightly with the spatula.
Cook for about 3-4 minutes on each side or until golden brown and crispy. Add more oil as needed for additional batches.
Transfer the cooked fritters to a plate lined with paper towels to drain excess oil.
Serve warm, optionally garnished with additional feta or chopped herbs.