Start by bringing a big pot of water to boil. Add the pasta and cook until al dente.
Heat a medium sized saute (frying) pan until hot. Add oil and when it begins to shimmer, just before the smoking point, add the onions and cook for 3 minutes over medium high heat.
Add the garlic and continue cooking until the onions become translucent. Do not let the garlic burn.
Add a quarter cup of the lobster stock to deglaze the pan. Add the lobster and the rest of the lobster stock.
Continue cooking until the lobster stock is reduced by half or to your desired thickness.
Add the chopped basil and parsley. Mount the butter in pieces off the heat. Mounting is where you add butter to a sauce at the end to give it texture, flavor and a sheen.
It is better to cut it up into smaller pieces and add one at a time while continuously stirring. You don't want to add all the butter at once.
Taste the sauce and season with salt and pepper.
When the pasta is done, drain it and add it to the sauce, mix all together and serve.