Place the broccoli into a large bowl OR place them directly onto a foil-lined baking sheet.
Add the onions and garlic cloves to the broccoli. Add the oil, nutmeg, salt and pepper to the vegetables and toss to evenly coat the veggies in oil and to distribute the seasonings.
Ensure the vegetables are in an even layer on the baking sheets and then roast them in the preheated oven for 15 minutes.
Remove the vegetables from the oven, stir them well and return them back into the oven to continue roasting for an additional 10-15 minutes, or until the edges of the broccoli become brown and caramelized. Remove from the oven and cool slightly.
To make the soup:
Heat oil and butter over medium/high heat in a Dutch oven (or soup pot) until melted. Stir in the all-purpose flour, along with the roasted broccoli, onion, and garlic and cook for 1-2 minutes stirring frequently.
Reduce the heat to medium and gradually add the chicken broth to the pot, stirring frequently. As the soup heats, you'll notice it thicken. After cooking for 10-15 minutes, use an immersion blender to carefully blend the soup to a creamy texture. *Safety Note - it is vitally important to keep the immersion blender under the surface of the soup while blending to prevent the hot soup from spraying all over the kitchen and the cook.
Once the soup is at your desired texture, stir in the shredded cheeses and allow to melt. Right before serving stir in the fresh lime juice for balance and brightness.
Ladle the soup into bowls and top with additional shredded cheese and croutons, if desired.
Video
Notes
*Safety Note - it is vitally important to keep the immersion blender under the surface of the soup while blending to prevent the hot soup from spraying all over the kitchen and the cook.Store any leftovers in an airtight container in the refrigerator for up to 5 days.Soup may be frozen. Store in airtight freezer containers or bags and freeze for up to 3 months.Thaw in the refrigerator overnight and reheat on the stovetop or covered slightly in the microwave.