Lentil Kielbasa Stew

• 3 onions (chopped)
• 2 lentils (dried)
• 2 kielbasa thinly (sliced)
• 1 bay leaf
• 1,400 ml beef stock boullion
• 130 gr carrots (chopped)
• 1 gr thyme
• 2 slices bacon (chopped)