Roasting tomatoes results in sweetness and complexity not evident when they are raw. Charred zucchini brings a little bitterness and crunchy texture. These define the character of this roasted tomato and zucchini soup.
Apart from using roasted tomatoes to make this soup, the other slightly unusual ingredient is the beetroot. We are not using the beetroot for its flavour but rather for the colour it imparts to the soup. However, it is sure to contribute some flavour as well. The actual beetroot is discarded before we blend the tomatoes.
Another natural way to enhance the red colour of a tomato soup is to add a teaspoon of ground annatto seeds. Using more paprika works well too. However, paprika brings along its own flavour profile, which may or may not be what you want.
Another feature to note is the use of egg yolks to thicken this roasted tomato soup. Using egg yolks, as opposed to the cornflour, imparts a lovely silkiness to the mouthfeel. Using egg yolks is such an underused thickening method.
Another recipe based around the sweet, complex flavour of roasted tomatoes is the sauce on this potato risotto al salto. The slow-roasted tomatoes bring add a sweet acidic counterpoint to the creamy, rich risotto.
This tomato zucchini soup works just as well in small quantities as an appetiser as it does in larger quantities for lunch or dinner, served with fresh baguettes.
Roasted tomato and zucchini soup
- 2 large zucchinis long rather than wide
- olive oil
- 5 Baguettes
- 4 slices cheese or 1/2 cup grated cheese
- 1/2 cup finely diced spring onions
- 1/2 cup parmesan
- Freshly ground black pepper
- Preheat the oven to 170 degC
- Halve the tomatoes and place on a baking tray, cut side up. Splatter some olive oil on them, and a sprinkling of salt.
- Trim the beetroot, smear with olive oil, and wrap in foil. Place on the baking tray.
- Prepare the head of garlic
- and place on the baking tray.
- Place the baking tray in the oven for one hour.
- Dice the onions and add to a large saucepan with the butter and a splash of olive oil.
- Saute the onions until translucent.
- Add the tomato paste and saute until its colour darkens.
- Allow the tomatoes, beetroot, and garlic to cool a little once finished cooking.
- Peel the beetroot, halve, and make a few cuts into the flesh. The beetroot if for the colour, We will discard it later.
- Squeeze the garlic cloves out of the skin, mash, and add to the saucepan.
- Add the beetroot and all the other soup ingredients except the egg yolks to the saucepan, and bring to a boil.
- Top and tail the zucchinis and add the offcuts to the soup as well.
- Reduce the heat and simmer for one hour.
- Slice the zucchinis into 5mm thick rounds
- Bring a skillet to a high heat and smear with cooking oil.
- In batches, char the zucchini slices on both sides. They should be charred, but still a little crisp to the bite.
- Remove from the skillet and put on a cold plate to stop the cooking. Zucchini are like eggs, so easy to overcook.
- Halve the baguettes length-ways.
- Sprinkle with spring onions and cheese.
- Grill in the oven for 15 minutes before serving.
- Finely grate the parmesan cheese
- Remove the beetroot, bay leaves, and zucchini off-cuts from the stock.
- Use an immersion blender to blend until no large lumps remain.
- Strain the stock through a strainer, pushing through some of the tomato flesh. What should remain is mostly tomato skins.
- Set aside 1 cup of the soup and allow to cool. Put in the freezer for a little while if you have a space in your freezer that is not adjacent to food items. Putting with the ice works well.
- Once the cup of soup you set aside is cool, whisk in the egg yolks.
- Add the egg yolk mixture to the soup, stirring well as you add it. Simmer for a few more minutes. The soup will thicken slightly.
- To serve, ladle some soup into a bowl. Carefully place some zucchini slices on the surface of the soup. Sprinkle with grated parmesan and freshly ground black pepper.