Pretty Tasty Crock Pot Pepper Steak

I am a wee bit if a food snob and soooooooo not a fan of crock pot cookery, but Grace requested this dish. And seeing as how I had no time to stand over the stove and watch it, into the crock pot it went.
Lo and behold! It was pretty darn good:

2 pounds beef sirloin steak or round steak, (cut on the bias against the grain) into 2 inch strips
3 tablespoons vegetable oil
1 medium onion, cut in half and then into thick slices
2 cloves garlic, minced
3 tb apple cider vinegar
1 tb beef bouillon
1/4 cup hot water
1 tablespoon cornstarch
1/2 cup chopped onion
2 large green bell peppers, halved and sliced thick
1 (14.5 ounce) can stewed tomatoes, with liquid
1/4 cup soy sauce
1 tsp Worcestershire sauce
1 teaspoon white sugar
1 teaspoon salt
Pepper to taste
Shake of hot sauce
DIRECTIONS
In medium dutch oven over medium high heat, heat the vegetable oil and brown the seasoned beef strips in two batches. Transfer to a slow cooker.
Place onions in dutch oven and continue to cook until softened, about 5 minutes. Add garlic, and sautee about 30 seconds. Add apple cider vinegar, beef bouillon, and water and deglaze the pan, scraping up brown bits from the pan. Sprinkle cornstarch on top, and stir.
Pour into the slow cooker with meat, add remaining ingredients, placing green peppers on top (stir them in half way, if you can).
Cover, and cook on High for 3 to 4 hours, or on Low for 6 to 8 hours.
Serve on top of mashed potatoes...