Cook the pasta until just al dente. Drain the tuna and roughly chop. Mix the pasta with the fish and peas and place in a casserole dish. In a bowl, mix the cream with the eggs and season with salt, pepper and nutmeg. Pour evenly over the pasta. Grate the Gouda and sprinkle evenly over the casserole. Bake in the oven at 180° C for 25-30 minutes until the cheese crust is golden brown.