Add the olive oil to a large skillet on Medium/High heat until hot.
Add the onion and season with salt and pepper.
Saute until the onion begins to become translucent and stir in the garlic; saute for around 1 minute.
Add the beef or turkey; salt and pepper to taste.
Break up the meat while cooking until browned.
Add the meat mixture to the bottom of a Slow Cooker.
Add diced tomatoes (drained), pureed tomatoes, pinto beans (drained), jalapeno pepper and beer; salt and pepper to taste.
Lightly stir ingredients.
Cook on high heat for 4-5 hours or low heat for 7-8 hours. Reduce heat and remove lid prior to serving to allow for it to thicken.