¼ medium red onion, chopped, plus thin slices for serving
1 large celery stalk, chopped
2 garlic cloves, smashed
¼ habanero chile, seeded
1 tablespoon chopped peeled ginger
½ teaspoon sugar
1 tablespoon kosher salt, plus more
⅓ cup coarsely chopped fresh cilantro
1 pound sea bass fillet, skin, bones, and bloodline removed
½ cup passion fruit juice or fresh orange juice, strained
½ cup (or more) fresh lime juice, strained
1 pound mixed heirloom tomatoes, whole or cut into wedges, depending on size
Microgreens (for serving)