Fry the bacon in 15ml of oil until browned and crisp, then drain on paper.
Squeeze sausagemeat from skins and add to the pan with sliced onions.
Cook mixture for 12 minutes, stir in both paprikas, and cook for one more minute.
Preheat oven to 200°C and butter a 2-litre ovenproof dish.
Boil 1.5 litres of salted water and stir in polenta for four minutes until thickened.
Melt butter and 75% of both cheeses into the polenta and season well.
Spread a third of the polenta into the dish and top with half the sausage and bacon.
Layer another third of polenta, the remaining meat, then the final polenta layer.
Scatter the remaining cheese and bake for 30 minutes until golden.