Lactose-free broccoli and cauliflower soup for a diet?

Do you prefer something thicker or lighter in consistency?

The key to getting it creamy without dairy is using other bases that give you that texture. What works best is blending the cooked broccoli and cauliflower with a bit of the broth, then pureeing it well, and then adding oat or soy milk (oat milk works better for this because it's naturally creamier). You can also use coconut cream, though that does change the flavor a bit. Some people use a splash of good olive oil and blend it all together, which also adds body without needing cream.

My trick is cooking the vegetables until they're really soft, then putting everything in the blender with some of the hot broth, and then straining it if you want it to be really smooth. Once you have that, you add the plant milk little by little until you get it to the consistency you want. Season well with salt, pepper, a touch of garlic or onion if you feel like it. If the soup ends up too thin, try adding a bit of boiled potato when you make the mixture - it thickens it without making the texture weird. And here's the important part: don't boil it on high heat once you've added the plant milk because some of them lose a bit of their creaminess.