Warmth a big saucepan to medium-high. Add butter and onion, and sauté till translucent. Season with ½ teaspoon salt and ¼ teaspoon pepper.
Add flour and stir till absorbed. Add vegetable broth and produce to a boil. Cut back warmth to simmer and stir regularly, 5 minutes.
Add potatoes and simmer till potatoes are simply tender. Add cream cheese and milk and 1 cup Colby Jack cheese. Cook dinner on low warmth, stirring typically, till soup is creamy and potatoes are totally cooked. Within the final 5 minutes of cooking time, add 1 cup frozen peas and extra salt and pepper, to style. Soup is prepared as soon as peas have heated via.
To serve, ladle soup right into a bowl. Prime with chopped bacon, inexperienced onion, and reserved cheese.