Melt butter in medium sauce pan over medium heat.
Add onions and cook 8-10 minutes, or until tender.
Add garlic and cook 1-2 minutes, or until fragrant.
Add tomato, chicken, cumin, salt, pepper, poblano peppers and stock and simmer for 8-10 minutes.
Whisk flour into half and half and add slowly to pan, stirring constantly until thickened.
Add cheese and stir until melted and incorporated.
Garnish individual servings as desired with tortilla strips, cilantro, additional grated cheese and poblano pepper.