Yes you can make it roasted courgette soup if you want. Make sure to cut onion into larger chunks (similar in size to courgette) and leave garlic cloves in there skins for roasting. Sprinkle over some olive oil and roast the veg in the preheated oven (180C/350F) for approx 30 minutes. Make sure to check on your veg from time to time and give it a stir half way through cooking. In the meantime put frozen peas in a pan you'll be finishing your soup in (or in a blender jug) and pour over hot veggie stock. Once your veggies finished roasting add them pot with stock and peas (make sure to squeeze the garlic out of their skins first) followed by beans and mint and some seasoning and blend.