In a large pot, bring to a boil the water, butter, lemon, garlic, parsley, salt, and peppercorns.
Add in the lobster tails and boil for 4 minutes.
Remove the lobster tails and set aside, then use a slotted spoon or mesh strainer to remove all of the other ingredients from the pot.
Once the liquid has been strained, drop in the uncooked pasta directly into the lobster stock. Add 1-2 more cups of water if needed.
Cook pasta according to package directions and strain.
In the same pot, heat up 3 tbsp of butter butter and add in the flour once the butter has melted. Whisk to combine.
Once the butter and flour mixture begins to foam up, pour in the milk and whisk.
Bring the milk to a simmer, whisking occasionally, until it begins to thicken enough to coat a wooden spoon.
Once it begins to thicken, add in the cheese, onion powder, garlic powder, salt and chives and whisk vigorously until the cheese has melted and the sauce is silky.
Break open the lobster tails and remove and coarsely chop the meat. Add the drained cooked pasta and lobster meat to the cheese sauce and fold everything together.
In another pan, melt the butter and add the minced garlic. Add in the Panko and cook until it toasts to a nice golden brown.
Add the Mac and cheese to individual serving dishes, or one large bowl, and top with the breadcrumbs and serve
OPTIONAL: place the serving dish (if oven safe) in a 400° oven for 5-7 minutes, then serve.