Step 1

Preheat oven to 200°C/180°C fan-forced.

Step 2

Melt butter in small saucepan over medium heat. Add flour. Cook, stirring, for 1 minute or until bubbling. Remove from heat. Gradually stir in milk until combined. Return to heat. Cook, stirring constantly, 3 minutes or until sauce boils and thickens. Remove from heat. Season with salt and pepper.

Step 3

Bring a medium saucepan of salted water to the boil. Add asparagus, zucchini and onion. Boil for 2 minutes. Remove with slotted spoon. Drain on paper towel. Add spinach to pan. Cook for 1 minute or until wilted. Remove with slotted spoon. Squeeze out excess moisture when cool enough to handle. Roughly chop.

Step 4

Cover the base of a 20cm x 28cm (8 cup- capacity) ovenproof dish with 2/3 cup white sauce. Layer 1/4 lasagne sheets trimming to fit. Layer asparagus mixture, peas and 1/3 ricotta. Top with 1/3 of remaining lasagne sheets, 1/2 spinach, and 1/2 remaining ricotta. Repeat. Top with remaining lasagne sheets and remaining white sauce. Arrange tomato and basil leaves on top. Sprinkle with cheese.

Step 5

Bake for 45 minutes or until golden and pasta is tender. Serve with extra basil leaves.