Preheat oven to 425°F / 200°C and line a baking sheet with parchment paper.
In a medium bowl, add the potatoes and cauliflower toss them with the olive oil, ras el hanout and cayenne, until evenly coated. Transfer them to the prepared baking sheet and spread in an even layer. Season with salt and pepper.
Roast, tossing once halfway through, until the edges of the cauliflower and potatoes are browned and slightly crisped, about 25-30 minutes.
Meanwhile, in a small bowl, add the ingredients for the herb-yoghurt sauce (yoghurt, herbs, lemon, garlic, salt and pepper) and mix together until well combined.
Remove cauliflower and potatoes from oven, transfer to a serving plate, sprinkle with a few extra herbs and drizzle with a little yoghurt sauce, serving the rest on the side for dipping or to drizzle on top, as desired. Enjoy!
For this recipe, I recommend Ral El Hanout from Lebensbaum. I also use my favourite go-to olive oil (Farchioni Olii S.p.A). It is heat resistant so works really well for roasting, frying and tastes great in salad dressings (both unpaid mentions!).
For a relaxing atmosphere in the kitchen I recommend my personal Elle Republic: Chilled Out Kitchen Tunes Playlist on Spotify.