Preheat your oven to 180C.

In an oven-safe pan, melt the butter over the stove. Stir in the flour.

Gradually pour in the milk, whisking continuously until it starts to bubble.

Add the grated cheese, a pinch of salt, and a sprinkle of pepper. Keep whisking until beautifully combined.

Now, fold in the drained tuna, cooked pasta, and frozen veggies. Mix it all up until everything's coated in that cheesy sauce.

Smooth the top and sprinkle over your choice of cornflakes or bread crumbs for that perfect crunch, or just extra cheese if you prefer.

Bake in the oven for about 15 minutes or until golden brown on top.