In a large frying pan, heat the olive oil. Add the chilli flakes, then add the tomatoes. Cook 3 mins more on a high heat until the tomatoes start to break down a little.
Add the lemon juice and cook for 1-2 mins. Remove from the heat and stir in the crab to warm through – not too much or it will break up.
Boil the gluten free pasta in a large pan of salted water following pack instructions then drain. Mix the pasta in the warm pot with the sauce, lemon zest, garlic oil and capers, and toss the basil through.