Dad's Creamy Cauliflower Soup

Bahan-bahan (4 porsi)

• 1 tbsp butter
• 1 tbsp unbleached flour (gluten-free is fine too)
• 1 medium head cauliflower (chopped)
• 1/2 cup chopped onions
• 4 cups less sodium chicken broth (vegetarians can use vegetable broth)
• salt and pepper to taste