In a large skillet over medium-high heat, add the oil.
2 tablespoons vegetable oil
Once the oil is hot, add the meat to the pan and pat it into an even layer. Allow to brown and flip, about 4 minutes. Continue to cook until about 3/4 of the way done. Transfer to a plate and set aside.
Lower the heat to medium. Melt the butter.
3 tablespoons unsalted butter
Add the onion and coat in the butter, cook for 10-15 minutes until the onions are softened and golden brown.
1 medium sweet onion
Add the garlic, rosemary, and thyme and cook for an additional 30 seconds until fragrant.