Preheat the oven to 220°C.
Heat the oil in an oven proof skillet over a medium-high heat. Add the onion and cook, stirring, until softened, about three minutes, then add the garlic and cook for one minute. Add the tomatoes and bring to a boil. Reduce the heat to medium-low and let simmer for about five minutes, until the tomato juices thicken.
Remove from the heat. Stir in the parsley, dill, and shrimp and season with salt and pepper. Sprinkle the feta over the top. Bake until the shrimp are cooked through and cheese melts, about 12 minutes.