Bring the milk with the bay leaf and onion to a simmer in a saucepan. Infuse off the heat for 20 minutes. Strain.
Meanwhile, cook the beans and peas in boiling water until tender: 6–8 minutes for fresh or 2 minutes for frozen. Drain and refresh in cold water. Process half in a food processor with the herbs and garlic to a rough purée. Combine with the ricotta, Parmesan and remaining vegetables. Season with salt and pepper.
Melt the butter in a saucepan over a very low heat. Add the flour and cook, stirring, for 2 minutes until a light biscuity colour. Remove from the heat and slowly add the infused milk, stirring away any lumps as you go. Return to the heat, bring to a simmer, stirring, and pour in the wine. Simmer for 5–6 minutes until thick. Season with salt and pepper.
Cook the pasta in a large saucepan of salted boiling water according to the packet instructions until just al dente. Drain, refresh in cold water, then cut into 16 pieces 8 x 9 cm (3¼ x 3½ inches).
Spread 1½ tablespoons of filling on to each pasta piece and roll up. Spread half the sauce in an ovenproof dish and top with the rolls in a single layer. Spoon over the remaining sauce. Sprinkle with Parmesan. Bake in a preheated oven, 200°C (400°F), Gas Mark 6, for 15 minutes until golden brown.