This is a relatively simple vegetarian lasagna that has a sweet taste, and has a fabulous flavour. It's a great dish, totally delicious and even kids who are a little unsure of vegetables are won over by this.
Cut eggplants lengthways into 1 cm slices; place slices on colander, sprinkle with salt,stand 30 minutes. Rinse slices under cold water, drain on absorbent paper. Cook eggplant in batches, in heated oil large pan until softened and browned both sides.
Cook onion and half the garlic in the same pan, stirring, until onion softens.
Stir in tomato, paste and basil; simmer, uncovered, about 20 minutes, or until thickened slightly. Blend or process tomato mixture until just combined.
Heat margarine in same pan, add leek and remaining garlic; cook, stirring, until leek is soft. Add sugar; cook, stirring, about 5 minutes or until leek is browned lightly, remove from heat.
Cut 1 lasagne sheet to cover base of oiled deep 19cm square ovenproof dish; place in position.
Top with 1/4 of the eggplant, 1/4 of the leek mixture,1/4 of the tomato mixture and 1/4 of the cheese.
Repeat layers 3 times, ending with cheese. Bake, uncovered, in moderately hot oven 50 minutes.
Can be made ahead to this stage. Cover, refrigerate until required. Reheat in moderate oven about 50 minutes.