Related Clues:

• Protein source
• Flesh
• Chili con carne ingredient
• Partner of potatoes
• Grouse
• Grumble
• Porterhouse, e.g.
• Fajita filler
• Gripe
• Substance
• Meat
• Spam, e.g.
• Muscle
• Good source of protein
• See 41-Across