Prepare the Tomato Water & Sashimi : Score a small 'X' on the bottom of all 5 beefsteak tomatoes. Blanch them in boiling water for 30-60 seconds, then transfer to an ice bath.
Peel the skins off. For the tomato water, roughly chop 3 of the tomatoes, season with ¼ to ½ teaspoon salt, and blend into a smooth purée.
Place in a cheesecloth-lined strainer set over a bowl and let it strain overnight in the refrigerator to collect the clear water.
Reserve the pulp for another use.
Prepare the Tomatoes for Sashimi : Take the remaining 2 peeled tomatoes, cut them in half, and gently scoop out the seeds. You should be left with the firm tomato petals. Thinly slice these petals into wide, sashimi-like pieces.
Make the Yuzu-Miso Dressing: In a bowl, combine ⅓ cup of the collected tomato water, the sweet white miso, crème fraîche, olive oil, and yuzu juice.
Whisk or blend until completely smooth and emulsified.
Season with salt and white pepper to taste. For the best flavor, let the dressing rest overnight in the refrigerator.
Make the Marinade: In a separate bowl, combine the sake, mirin, soy sauce, yuzu juice, and the piece of kombu seaweed.
Stir to combine and let this mixture also rest overnight in the refrigerator to allow the flavors to meld.
Marinate & Serve: Remove the kombu from the marinade. Gently place the prepared tomato slices into the marinade bath for 5-10 minutes to absorb the flavor. To serve, spread a thin, round layer of the yuzu-miso dressing on each plate. Carefully lift the tomato slices from the bath, letting any excess liquid drip off.
Arrange the tomato sashimi beautifully over the dressing and garnish with a sprinkle of fresh micro greens and herbs.
Don't discard the tomato pulp left over from making the tomato water! It's packed with flavor and perfect for adding to pasta sauces, soups, or bruschetta.