Finely chop the onion and sauté in a tablespoon of oil over medium heat until golden and fragrant, about 3-4 minutes. Let it cool slightly.
Rinse the fresh spinach leaves thoroughly, then squeeze out all excess moisture using a clean towel or paper towels. Roughly chop the drained spinach.
In a large mixing bowl, combine the chopped spinach, sautéed onion, toasted breadcrumbs, and a beaten egg. Add salt, pepper, and cumin if using, then mix everything thoroughly until the mixture sticks together when pressed.
Shape the mixture into about 8-10 small patties, roughly 1 inch thick, pressing firmly to ensure they hold together.
Heat 2 tablespoons of oil in a frying pan over medium heat until shimmering and hot, around 160°C (320°F). Carefully place the patties into the pan, leaving space between them.
Cook the patties for about 3-4 minutes on each side, flipping gently with a spatula, until they are golden brown and crispy on the outside.
Once crispy and golden, transfer the cutlets onto a paper towel-lined plate to drain excess oil. Continue frying the remaining patties in batches, adding more oil if needed.
Squeeze fresh lemon juice over the hot cutlets to brighten the flavor, and serve immediately while they’re still crispy and warm.
