Dice the onion.
In a large saucepan, add the onion and butter. Cook on medium heat until nearly translucent.
While the onion is cooking, dice the poblano and jalapeno.
Once the onion is almost done cooking, add the poblano, jalapeno, and salt. Cook until the onion is fully translucent and the peppers have just begun to cook. This should take just a couple minutes.
Mince the garlic and dice the tomatoes.
Add the garlic and tomatoes to the saucepan and cook until the garlic is fragrant, roughly 30 seconds.
Add the flour and mix until it is evenly incorporated.
1/4 cup at a time, add the milk. Stir after each addition until the the mixture has begun to thicken.
Reduce the heat to low. Add the cheese and mix until it is fully combined. You can take the pan entirely off the heat if the milk mixture is close to simmering or turn up the heat slightly if the cheese needs more warmth to melt.
Enjoy!
