Just in case anyone else wants to try it. Very easy.
500g tin tuna, drained
500g dried pasta
500g grated cheese (mature cheddar works best)
1 jar carbonara pasta sauce
1 jar bolognaise pasta sauce

Cook pasta until nearly cooked, still firm to bite.
Drain, and mix in the tomato pasta sauce
In a bowl mix together the tuna, carbonara sauce, and
approx 1/2 the cheese.

Layer an ovenproof dish with the mix:
1/3rd tomato pasta
1/2th the carbonara tuna
1/3rd pasta
other 1/2th tuna
Last 1/3rd pasta
Top with remaining grated cheese
Bake in medium oven until cheese has melted (approx 15 mins)

Eat.