I'd do what I did. Use the $100,000 as collateral (never SPEND your capital, keep it and get a low interest business loan: I started with virtually nothing) and buy a few franchised sandwich shops. Have the loan paid off in 4-6 years, sell out and walk away with 500,000+... plus your profits, or keep the stores, and use them as collateral for more shops. The key is finding good store managers at first. Then when you expand, finding a good general manager.
If you're not growing, you might as well sell, invest the money, and work for someone else. Buying a single business and working at it only earns a living, it never makes you money.