1. Preheat your oven to 220°C/Fan 200°C/Gas 7. Fill and boil your kettle. Trim and discard any ragged leaves from the cauliflower, then remove any remaining leaves and set them aside. Trim the base off the cauliflower and cut the cauliflower into 1½cm-thick slices. Line a baking tray with baking paper and add the cauliflower slices, along with any broken florets.
2. Tip 1 tbsp Spanish seasoning into a small bowl and pour in 1 tbsp olive oil and the yogurt. Add a good pinch of salt and pepper and stir together. No Spanish seasoning? Use a mix of paprika, saffron and black pepper, or try using your favourite spice blend, such as fajita seasoning, Cajun ragin' or mixed herbs.
3. Spoon the spiced yogurt over the cauliflower steaks and loose florets. Slide the tray into the oven to roast for 20 mins, then add the cauliflower leaves to the tray and roast for another 15 mins.
4. While the cauliflower roasts, tip the lentils into a pan and cover with plenty of hot water from the kettle. Add a pinch of salt, pop on a lid and simmer on a medium heat for 20 mins.
5. While the cauliflower and lentils are cooking, make the salsa. Peel and finely chop the red onion and pop it into a bowl. Add 2 tbsp red wine vinegar and a pinch of salt and scrunch together with your hands. Quarter the cherry tomatoes and place them on top of the onions. Halve the chilli and flick out the seeds. Finely chop the chilli and add it to the bowl. Finely chop the mint leaves and add those, but don't mix them in. Drain and rinse 1 tbsp capers and add them to the bowl. Set to one side, not mixing just yet.
6. After 20 mins, check the lentils. They should be soft with a slight bite. Cook them for a little longer, if you need to. Drain and tip them back into the pan. Stir the salsa ingredients together, then add half the salsa to the lentils and stir to mix. Pop the lid on the pan to keep the lentils warm.
7. When the cauliflower has cooked for 35 mins total, it should be tender when pierced with the tip of the knife, and darkening at the edges. The yogurt will be thick, deep orange and lightly caramelised, and the leaves crispy and golden. Remove the tray from the oven. Divide the lentils between a couple of plates. Top with a few cauliflower steaks each and the remaining salsa. Serve straight away.