Perfect summertime cold soup to showcase those beautiful heirloom tomatoes from your garden. If you want to add some fresh garlic, be my guest. Wonderful Italian, French and Spanish flavors! Try other cheese in place of Gruyere-manchego, asiago, French feta... Local recipe.
Heat the butter and olive oil (you can use either or both) in a large stock pot. Saute the onion until the onion is softened and translucent. Add the fresh tomatoes, (tomato puree if using), sugar, and vegetable broth. Cook over medium heat for about 15-20 minutes or until soft. Do not boil! Set aside to cool slightly.
Puree the tomato mixture in a food processor in batches (to avoid burning yourself!). Note: if you want to remove the tomato seeds you can push the tomatoes through a strainer first. Stir in the Spanish smoked paprika and salt to taste. For a creamier texture, whisk in 2 tablespoons half and half cream or sour cream (heavy cream will work, too.) Set aside.
Place the baguette slices on a parchment-lined baking sheet. BROIL the bread 6" from the heating element until lightly toasted on both sides, approximately 2 minutes total. Top the toast slices with the Gruyere and broil for *about* 30 seconds or until the cheese has melted and is bubbly. Watch carefully!
To serve: Ladle a portion of the soup into each soup bowl. Place a Gruyere toast slice on top, add some chiffonade of fresh basil, drizzle of balsamic vinegar and extra virgin olive oil. If desired a few cherry tomato halves on top. Serve the remaining Gruyere toast slices on a platter.
Tip: Sometimes-(as with gazpacho soup, for example), I will add 1-2 ice cubes to each soup bowl serving to keep the soup well chilled. This is optional but is offered as a suggestion.