Cook the pasta according to directions to al dente. Drain and set aside.

Melt the butter in a large saute pan or pot. Add in the onion and minced garlic and saute over medium heat until tender.

Add the shrimp, imitation crab, old bay seasoning, salt and pepper, broth, hot water, and bouillon base. Simmer until the shrimp are opaque. Stir to break up crab meat.

In a medium bowl, whisk together sour cream and flour. Add to the seafood mixture and mix well. Reduce heat to low and let summer until thick and bubbly.

Remove from heat and stir in pasta. Let set with lid on for 15-20 minutes. Serve with fresh basil or cilantro as a garnish.