For the crab spaghetti, bring a large pan of salted water to the boil and cook the spaghetti according to packet instructions. Drain and keep warm, reserving 150ml of the cooking water.
Melt the butter and olive oil in a large pan. Add the garlic and cook for 30 seconds, stirring constantly, until fragrant. Add the white wine, lemon juice and chopped chilli. Bring to the boil, reduce the heat and simmer for 5 minutes until the wine has reduced by half.
Add the crabmeat and hot spaghetti and mix together. Add 75g of Parmesan and toss together. Add the reserved cooking liquid a little at a time if the pasta needs more liquid.
For the gremolata, melt the butter in a frying pan over a medium high heat. Add the breadcrumbs and salt and cook for 3-5 minutes, stirring occasionally until the breadcrumbs are lightly toasted.
Remove from the heat and add the garlic, parsley and lemon zest. Sprinkle over the crab spaghetti and top with the remaining Parmesan cheese. Garnish with chopped parsley and lemon zest.