Blanche the kale in boiling salt water for around 5 min. Quench, drain and chop.
Fry the onion and garlic in 2 tbsp of the artichoke heart oil for 1-2 min. Stir in the kale and the artichokes, season with salt and ground black pepper and add the wine. Cover and simmer for around 10 min.
Remove the lid, allow the liquid to evaporate, season to taste and leave to cool.
Preheat the grill.
Drizzle the bread with some olive oil and grill on both sides for 2-3 min. Remove from the grill, leave to cool.
Spread with the mascarpone, add the cabbage mixture and serve.