This sweet potato soup is silky smooth and packed with the deeply satisfying flavours of beautifully caramelized oven-roasted veggies and warming spices. All you need is a sheet pan and a blender.
On a large sheet pan prepared with a silicone mat, parchment, or greased foil, add the cubed sweet potatoes and the onions. Drizzle the oil over the vegetables. Season with fresh ground sea salt and black pepper. Rub the seasonings and oil into the vegetables and spread them out. Add the garlic and thyme sprigs alongside the vegetables at this point.
Roast for 25 to 30 minutes, turning halfway, until veggies are roasted and sweet potatoes are cooked through.
Remove from the oven and remove the skins from the garlic.
In a large blender, add all the remaining ingredients with the vegetables (if your thyme isn't dried out, you can pick the leaves off the stems and add that in too). Ensure that the broth is very hot. If you're not using a large blender (holds at least 6 cups), then do this in increments.
Using the soup setting on your blender, or a very powerful blend option, blend until creamy and smooth. My blender automatically blends for about 3 minutes continuously.
Taste and add salt and pepper to taste if necessary.
Top with garnish (I used some thyme leaves that I removed from their stems and some extra cinnamon).
Serve into bowls and enjoy!
Notes
Discard. Don't forget to toss the garlic skins and remove as much of the thyme stems as possible after roasting and before adding everything to the blender.
Hot broth. The broth needs to be nice and hot to break down the veggies, and so it doesn't cool down the soup.
Don't overload the blender. If your blender can’t accommodate 6 cups, blend in batches.
Give it a taste. Give your soup a taste before serving and adjust the seasonings as you see fit.
Storage. Seal fully cooled leftover soup in an airtight container, such as a mason jar, and store it in the fridge for up to 4 days or in the freezer for up to 3 months. Thaw in the fridge and reheat on the stove over medium-low heat, stirring occasionally. Run the soup through the blender to restore its extra-creamy texture.