Melt butter over medium heat in large dutch oven on stove top.
Add diced onion, garlic, & bell pepper.
Saute 5 - 8 minutes till translucent.
Mix in cornstarch & dry mustard till incorporated well.
Add veggie broth, cream cheese & half & half cream.
Cook until thickened about 12-15 minutes.
Add pimentos, grated cheese, cayenne, & salt & pepper to taste.
Cook another couple minutes till cheese thoroughly melted.
Taste for salt & pepper.
optional:
Can garnish with additional diced red bell pepper & chopped parsley.