Preheat oven to 180C/350F.

Cook pasta according to packet directions. Drain and pour into baking dish.

Heat 1 tbsp oil in a skillet over very high heat. Add seafood and sear for 30 seconds, turn then sear the other side for 30 seconds (should still be raw inside). Remove into baking dish.

Return pan to stove, add remaining 1/2 tbsp oil and turn down to medium. Cook leeks and garlic for 3 minutes or until soft. Add to baking dish.

Mix pasta, seafood and leeks together in the baking dish.

Melt butter in the skillet. Add flour and mix into the butter. Cook for 1 minute,

Add 1 cup of milk and use a whisk to combine - it will thicken quickly. Add remaining milk and bouillon cube (crumbled) and whisk to combine. Cook, whisking occasionally at first then constantly as it thickens, for around 5 minutes or until the sauce is thick enough to coat the back of a wooden spoon (see photo in post). Season with salt and pepper.

Pour into the baking dish. Top with panko and parmesan.

Bake for 20 - 25 minutes, or until the top is golden.

Rest for 5 minutes before serving, garnished with fresh parsley if desired.

I served this with garlic spinach (Note 2).