To make sauce, saute onions and garlic in hot oil until tender, but not brown, in large saucepan

Add tomatoes, stir and let come to a boil

Lower heat and simmer gently for 30 minutes

Add Pesto

Cook for another 5 minutes

Meanwhile, cut under-shells of lobsters lengthwise, leaving top shell intact

Remove lobster meat whole and wash thor- oughly

Add lobster meat to sauce

Simmer for about 20 minutes, covered. Meanwhile cook spaghetti until al dente, drain, and arrange in center of a heated serving platter

Remove lobster tails from sauce then pour sauce over cooked spaghetti

Sprinkle with Parmesan cheese

Arrange lobster meat around spaghetti with sauce

Serve immediately

Serves 4 to 6.