Soak lentils in
cold water for 2 hours, then rinse and drain well. Preheat the oven to
moderate 180C. Heat oil in frying pan; add the leek and garlic and cook
for 3 minutes or until soft. Add the ground paprika and oregano and cook
for 2 minutes or until fragrant. Place in a 10-cup capacity casserole dish
along with the celery, zucchini, capsicum, eggplant, potatoes, vegetable
stock, canned tomatoes and tomato paste. Cover and cook casserole for 90
minutes, stirring occasionally. Season well with salt and pepper.