Step 1 : Heat 1 tbs of the oil in a shallow casserole dish over medium heat. Add the onion, basil stems and half the garlic. Cook, stirring, for 4 minutes or until softened. Transfer to a bowl. Step 2: Add 1 tbs oil and prawns to dish over medium-high heat. Season. Cook, stirring, for 2 minutes. Add rind, chilli and remaining garlic. Cook, stirring, for 1 minute or until aromatic. Transfer prawn mixture to a bowl. Set aside. Step 3: Return onion mixture to dish over medium heat. Add risoni and cook, stirring, for 1 minute or until coated. Add stock and lemon juice. Cook, stirring regularly, for 12-14 minutes or until risoni is al dente and liquid is almost all absorbed. Step 4: Meanwhile, preheat oven grill to high. Line a baking tray with foil. Place asparagus and tomato on tray. Drizzle with remaining 1 tbs oil. Season. Cook for 4-5 minutes. Step 5: Stir the prawn mixture, half the vegetable mixture and the basil leaves into the risoni, until warmed through. Remove from heat. Top with remaining vegetable mixture and basil.