500 gm dried penne
60 ml (¼ cup) olive oil
3 garlic cloves, finely chopped
1 tbsp rosemary
24 uncooked prawns, peeled, deveined and coarsely chopped
3 birdseye chillies, or to taste, finely chopped
600 gm tomato polpa
To serve: coarsely chopped flat-leaf parsley

80 gm sourdough crumbs
20 gm butter
1½ tbsp olive oil
1 garlic clove, crushed

Cook penne in a saucepan of well-salted boiling water until al dente (10–14 minutes), then drain, reserving a little pasta water.

Meanwhile, for toasted crumbs, combine ingredients except garlic in a large deep frying pan over medium heat until toasted, stirring in garlic in the last minute (4–5 minutes).
Transfer to a plate and wipe out pan.

Heat olive oil in pan over medium heat, sauté garlic and rosemary until fragrant (1–2 minutes), then add prawns and chillies and stir until just starting to turn opaque (1 minute).
Add polpa, bring to a simmer, season to taste and simmer until sauce is well flavoured, and prawns are cooked (2–3 minutes).

Add pasta to sauce, toss to combine and loosen with a little pasta water if necessary.
Serve scattered with toasted crumbs and parsley.