Catalana Shrimp

Method

1. Peel and cut the sweet potato and yellow potato into similar-sized pieces.
2. Boil salted water. Add sweet potato first, after 3 minutes add yellow potato. Cook until tender, then drain.
3. Cut the three types of tomatoes into wedges.
4. Blanch the Tropea onion in boiling water with white wine vinegar for a few seconds, then drain.
5. Season the tomatoes with salt, olive oil, black pepper, and torn basil leaves.
6. Season the drained onion with salt, olive oil, and a pinch of sugar.
7. Peel the pink shrimp, crushing the heads into a bowl. Remove the vein.
8. Quickly blanch the shrimp in boiling salted water for about 30 seconds to 1 minute, then drain.
9. Make the sauce: mix the crushed shrimp heads with lime juice, olive oil, and salt.
10. Plate: arrange the potatoes (unseasoned), tomatoes, shrimp, onion, basil leaves, and drizzle with the sauce.
11. Mix everything together before eating.