Baked Halibut with Jammy Tomatoes

Ingredients

• 1 ½ pints cherry tomatoes (about 3 cups)
• 1 medium yellow onion, thinly sliced
• 3 garlic cloves, thinly sliced
• 3 tbsp olive oil, divided
• 1 tsp sea salt
• ½ tsp freshly cracked black pepper
• ½ tsp red pepper flakes (optional)
• 2 sprigs fresh thyme (or ½ tsp dried)
• 2 sprigs fresh oregano (or ½ tsp dried)
• 1 lemon (zest + wedges for serving)
• 1 ½ lb halibut filet, skin on or off, cut into 2–3 portions
• Flaky sea salt, for finishing