Add the corn, milk, butter, and flour to a mixer and blend the ingredients into a fine puree. Next, pass everything through a sieve into a pot, cook it for a short while, and season with salt and nutmeg.
Fry the onions and garlic in olive oil. Next, add the shredded chicken, tomato sauce, sour cream, corn, thyme, and rosemary to the pan before seasoning everything with salt and pepper. Leave the mixture to simmer.
Place a slice of gouda on top of each lasagna sheet, add two tablespoons of the filling onto each slice of cheese, and finish by rolling the entire thing up into a cannelloni. Place your five giant cannelloni in a casserole dish.
Sprinkle mozzarella onto the cannelloni and pour the corn and béchamel sauce on top. Next, grate some parmesan on top and place the casserole dish in a convection oven set to 370°F for 13 minutes.
