Dunkin Brands' (DNKN +0.5%) business model is built for stability rather than speed, so Heard On The Street says the stock deserves another helping. DNKN has a clear plan to expand to the western half of the U.S., where it still has a small presence, and the stock is a smart play on the K-cup craze, which accounted for 30% of same-store sales growth in Q4.