Heat the oil in a large heavy based pot with a lid over high heat.

Cook vegetables - Cook the onion and garlic for 2 minutes. Add the beef and cook, breaking it up as you go, until you no longer see red meat. Add the carrot and zucchini, cook for 2 minutes until the water they release mostly evaporates. Add the capsicum and cook for 2 minutes.

Spices - Add the tomato paste and Cajun Spices. Cook for 1 minute.

Pasta sauce - Add the canned tomato, water (I swill the cans clean), stock and beans. Mix and bring to a simmer.

Add the pasta, stir, let it come back up to the simmer. Put the lid on and lower the heat slightly to medium so the liquid is simmering (not bubbling madly).

Cook for 15 minutes, stirring every few minutes so the base doesn't catch. The pasta should be a bit firmer than you want in the middle, and still a bit soupy which is good! Liquid gets absorbed in the next step.

Melt cheese - Give it a stir, smooth the surface, sprinkle with cheese. Put the lid on then turn the stove off (leave the pot on the stove). Leave for 3 minutes so the residual heat melts the cheese and the pasta finishes cooking.

Serve - Remove from the stove, sprinkle with green onion if desired, then serve immediately while saucy and the cheese is gooey!