The oven does all the work—plus a secret ingredient that turns winter tomatoes into flavour bombs
After weeks of cookies, chocolate, and butter in every form, I’m officially ready for soup. Baking, packaging, and mailing more than 30 holiday cookie boxes will do that. I’m craving something warm, savoury, and unfussy. This one-pan roasted tomato soup lets the oven do the heavy lifting, turning winter tomatoes into flavour bombs with very little effort. Serve it with grilled cheese dippers, and you’ve got comfort food that feels restorative, not indulgent.
The secret is a small step that completely changes the flavour of winter tomatoes—and it all happens in the oven.
The magic ingredient here is tomato powder—an intensely concentrated form of tomato that completely transforms bland winter tomatoes. Tomato powder is exactly what it sounds like—tomatoes that have been slowly dried and ground into a fine powder. It’s deeply concentrated and savoury. It’s one of my favourite ways to boost tomato flavour when fresh tomatoes are out of season. You’ll likely need to order it online, but it’s absolutely worth the trouble. A small amount goes a long way. When it hits the heat of the oven, it melts into the tomatoes, amplifying their natural sweetness and umami as they roast. Think of it as a flavour insurance policy for winter cooking.
Keys to Success
- Don’t crowd the pan: Give the tomatoes and shallots plenty of space on the sheet pan. Crowding leads to steaming instead of roasting, which means less caramelization and less flavour.
- Tomato powder goes on before roasting: Sprinkling the tomato powder onto the tomatoes before they go into the oven is key. Heat helps it dissolve and meld with the tomatoes as they roast, creating deeper, more concentrated flavour than adding it later.
- Roast until collapsed and jammy: You’re not just softening the tomatoes—you’re concentrating them. Look for wrinkled skins, lightly caramelized edges, and a pan that smells rich and savoury. If needed, give them a few extra minutes.
- Peel the skins before blending: Roasting loosens the skins, making them easy to remove. Taking a minute to peel them off ensures a smoother, silkier soup.
- Blend thoroughly, then adjust: Blend the soup until completely smooth, then taste. This is the moment to adjust salt or spice before adding the cream.
- Go low and slow with the grilled cheese: Medium-low heat is your friend. It allows the bread to turn deeply golden while giving the cheese time to melt fully—perfect for dunking.
If You Don’t Have Tomato Powder
Tomato powder delivers the deepest flavour here, but if you don’t have it, tomato paste is the best substitute.
- Use 2 tablespoons double-concentrated tomato paste
- Mix it with the olive oil and seasonings before tossing with the tomatoes
- Roast as directed
The flavour won’t be quite as intense, but roasting will still coax out plenty of sweetness and depth.
If you cook with tomatoes often in winter, tomato powder is worth ordering—it’s shelf-stable, lasts a long time, and adds instant flavour to soups, sauces, and stews.
One-Pan Roasted Tomato Soup with Grilled Cheese Dippers
Ingredients
Soup
- 2 Tablespoons Tomato Powder
- 1 teaspoon Diamond Crystal Kosher salt, optional (omit if your tomato powder already contains salt)
- 1/2 teaspoon Aleppo pepper or red pepper flakes
- 2 Tablespoons light brown sugar
- 1/2 teaspoon black pepper
- 1.8 kilograms plum tomatoes, about 30 tomatoes, halved lengthwise
- 6 shallots, peeled and halved lengthwise
- 3 cloves garlic, do not peel
- 2 large sprigs fresh thyme
- 2 Tablespoons olive oil
- 1/2 cup 35% cream
Basil Oil (optional)
- 50 grams fresh basil leaves
- 25 grams fresh spinach leaves
- 1 cup neutral vegetable oil, sunflower or safflower
Grilled Cheese Sandwiches
- 8 slices bread, (Pepperidge Farm Jewish Rye & Pumpernickel Deli Swirl works beautifully)
- 8 ounces Gruyere cheese, grated
- 3 Tablespoons unsalted butter, softened
Instructions
Make the Soup:
- Preheat the oven to 400°F.
- In a small bowl, mix the tomato powder, salt (if needed), Aleppo pepper, brown sugar, and black pepper. Set aside.
- Arrange the halved tomatoes, shallots, and unpeeled garlic cloves on a rimmed half-sheet pan.Sprinkle evenly with the seasoning mixture, drizzle with olive oil, and toss well using your hands to ensure everything is coated.Tuck the thyme sprigs among the vegetables.
- Roast for 35–40 minutes, until the tomatoes are collapsed, lightly caramelized, and intensely fragrant.
- Remove from the oven and let cool slightly.Slip off and discard the tomato skins. Squeeze the roasted garlic from its skins and discard the papery shells. Remove and discard the thyme stems.
- Transfer everything to a blender and blend on high until completely smooth.
- Pour the soup into a medium saucepan, whisk in the cream, and gently reheat over medium-low heat. Taste and adjust seasoning if needed. Keep warm.
Make Basil Oil (optional)
- Place basil, spinach, and oil into blender. Blend for 2-3 minutes until very smooth. Line a fine mesh strainer with a single layer of cheesecloth. Set strainer over a large bowl. Strain basil oil. Discard basil/spinach solids.
Make Grilled Cheese Dippers:
- Butter one side of each slice of bread. Place four slices butter-side down on a baking sheet.Divide the grated cheese evenly among them, then top with the remaining bread slices, butter-side up.
- Heat a nonstick skillet over medium-low heat.Cook the sandwiches until the first side is golden brown. Flip, cover the pan, and cook until the cheese is fully melted and the second side is deeply golden. Depending on the size of your pan, you may need to do this in 2 batches.
- Transfer to a cutting board and slice into 2-inch strips.
To Serve:
- Ladle the hot soup into bowls, drizzle with basil oil, if using and serve with grilled cheese dippers for dunking.
Notes
- The basil oil for drizzling onto the finished soup is completely optional. I think it makes for a beautiful presentation, but feel free to leave it out and just garnish with thinly sliced fresh basil leaves instead.