Homemade Thai Curry Peanut Sauce

I'm so excited! I was wanting the Thai Peanut Curry Chicken I made about two weeks ago, but didn't have the store-bought Taste of Thai Peanut Sauce...bummer! BUT, I found a recipe online (several actually), and the first one I tried is EXACTLY what I was shooting for! I changed it a bit, so I'm listing my changes, but the original recipe was found here.

Ingredients:
1 Tbsp olive oil
1 1/2 Tbsp minced garlic
2 Tbsp red curry paste
1 1/4 cups creamy peanut butter
1/2 cup brown sugar
1/2 tsp chili powder
1/2 tsp cayenne pepper
1/2 Tbsp fish sauce
1 tsp sesame oil
2 - 13.5 oz cans coconut milk
1/2 cup milk
1 cup sliced red/orange bell peppers
1/2 cup diced onion
1/2 - 1 cup cooked chicken, pulled apart
crushed peanuts, optional
rice noodles

Directions:
1. Soak rice noodles in large bowl with lots of water for about 20 minutes.
2. While soaking, heat the oil in a large skillet over medium heat. Stir in the garlic, and cook about one minute, being careful not to burn. Add the red curry paste, and stir for 1 minute more. Whisk in the peanut butter, brown sugar, chili powder, cayenne pepper, fish sauce, sesame oil, and coconut milk. Bring to a simmer, whisking occasionally, until sauce has thickened and is smooth.
3. Add peppers, onion, and chicken and cook until peppers are soft. (I freeze my sliced peppers to have on hand, so they soften up very quickly, so not sure of the exact amount of time with fresh peppers).
4. Drain noodles, and add them to the peanut sauce. Heat through.