What can I use instead of Sriracha if I only want to make a dish non-spicy, but similarly flavorful? The specific recipe I'm making is http://www.budgetbytes.com/2012/08/spicy-noodles/ (copied at bottom for posterity). 

I'm a big fan of the spice, but my guests and partner are often not. Since the sriracha is a critical part of the sauce, and makes the noodles quite spicy, I'd like to somehow avoid the spicy effect, while keeping the flavor, texture, and if possible color, reasonably similar. The dish is alright if you simply remove the sriracha and keep the soy sauce and brown sugar, but it's not as flavorful. Is there anything that is similarly flavorful that I could use, but that doesn't have the spice?

I've also tried an equal amount tomato paste, and holy crap was that a mistake. There might be some other way to use tomatoes, though.


  Ingredients
  
  
  4 oz. lo mein noodles $1.13
  2 Tbsp butter $0.20
  ¼ tsp crushed red pepper $0.02
  1 large egg $0.25
  1 Tbsp brown sugar $0.02
  1 Tbsp soy sauce $0.02
  1 Tbsp sriracha (rooster sauce) $0.08
  1 handful fresh cilantro $0.22
  1 sliced green onion $0.06
  
  
  Instructions
  
  
  Begin to boil water for the noodles. Once the water reaches a full boil, add the noodles and cook according to the package directions (boil for 5-7 minutes).
  While waiting for the water to boil, prepare the sauce. In a small bowl stir together the brown sugar, soy sauce, and sriracha.
  In a large skillet melt 2 tablespoons of butter over medium-low heat. Add the red pepper to the butter as it melts. Whisk an egg in a bowl and then add to the melted butter. Stir gently and cook through. Once the egg is done cooking, turn off the heat.
  When the noodles are tender, drain the water and then add them to the skillet with the cooked egg. Also add the prepared sauce. Turn the heat on to low to evaporate excess moisture, and stir until everything is coated well with the sauce. Sprinkle the sliced green onions and cilantro leaves (whole) on top and serve!
  ```
There are a lot of things you could add that would deliver a similar pepper and garlic flavor.  One thing that comes to mind is Ajvar.  It's a Serbian relish made primarily from red bell peppers, garlic, and eggplant.  I live in the US, and the local supermarket carries it in both mild and spicy versions.  Aside from being a lot milder, the flavor profile is pretty similar to sriracha sauce.

If you don't mind doing some more work, you could roast, skin, and mash some red bell peppers yourself.  Then add some garlic, a bit of something sweet (optional), and some hot pepper (also optional).