Grilled Tomato Sauce with Tuna

Ingredients

• • 1/2 cup (125 ml) chopped celery
  • 1 clove garlic, finely chopped
  • 1 tablespoon (15 ml) olive oil
  • 4 cups (1 litre) grilled tomato sauce
  • 1/4 cup (60 ml) oil-packed black olives, drained, pitted and quartered
  • 1 can 7oz (198 g) tuna chunks in water, drained
  • 1 green onion, thinly sliced
  • Salt and pepper