In a large skillet, heat oil over medium heat.
Sear sausage for 3-5 minutes on both sides.
Remove sausages from skillet and reserve on plate.
Drain all but 1 Tbsp. of fat from the pan. Return skillet to heat and add 1 Tbsp. butter.
Sauté garlic and onions until golden brown.
Add green chile sauce and beer. Stir to combine.
Add seared sausages to sauce. Cover and simmer on medium heat for 15-20 minutes until sausages are thoroughly cooked.
Remove sausages from skillet. Reserve.
Cook sauce, uncovered, for 10 additional minutes until reduced.
In a separate skillet, lightly toast hot dog buns with remaining butter.
Place sausages in buns. Top with sauce.