Heat your oven to 220°C/Fan 200°C/Gas 7. Place a baking tray in the oven to warm up.
Slice the sweet potatoes into 1 cm thick slices, then cut the slices into 1 cm thick chips. Tip into a bowl with 2 tbsp oil and some salt and pepper. Toss to coat in the oil. Tumble the sweet potatoes onto the warm baking tray.
Add the cherry tomatoes to the tray. Roast for 25 mins till the chips are tender and the tomatoes bursting from their skins.
Peel and grate the garlic. Zest the lemon. Place in a small bowl. Stir in 1 tsp smoked paprika and 1 tbsp oil. Season with salt and pepper. Mix together.
Place the salmon fillets in a baking dish, skin-side down. Rub the paprika oil all over the salmon.
When the potatoes have cooked for 15 mins, slide the salmon into the oven, on a shelf below the sweet potatoes. Cook for 15 mins.
Check the salmon is cooked by inserting a sharp knife into the thickest part. The flesh should be opaque. If not, cook it for another 2 mins.
Put a handful of spinach on each plate. Place the smoky Spanish salmon on top and serve with the sweet potato chips, tomatoes and lemon wedges for squeezing.