Achiote-Grilled Fish Tostadas with Pickled Red Onion

By , Test Kitchen Director · Reviewed by AislePrompt Editorial · ·

Fresh white fish marinated in achiote and grilled to perfection, served on crispy tostadas topped with zesty pickled red onions and fresh herbs. This mexican-inspired seafood ready in about 50 minutes pairs white fish fillets (tilapia or cod), achiote paste, orange juice for a weeknight-friendly dinner that comes together with one pan and minimal cleanup. Each serving lands at about 320 calories and feeds 4, so it slots cleanly into a weekly meal plan and pairs well with a quick salad or grain on the side. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.

Prep: 40 min Cook: 10 min Serves 4 Mexican cuisine 320 cal/serving
Build a week of meals around this recipe → Shop this recipe on Instacart → Shop equipment ↓

Ingredients

Equipment for this recipe

Top-rated tools to make this recipe successfully.

More Knives & cutting boards → Shop all kitchen tools →

Instructions

  1. Step 1: In a bowl, whisk together 2 tbsp achiote paste, 1/4 cup orange juice, 2 minced garlic cloves, and 2 tbsp vegetable oil. Add 1 lb white fish fillets and coat thoroughly. Marinate for 30 minutes in the refrigerator.
  2. Step 2: Meanwhile, combine 1/2 cup white vinegar, 1 tbsp sugar, 1 tsp salt, and 1 medium thinly sliced red onion in a jar. Let sit at room temperature for at least 30 minutes to pickle.
  3. Step 3: Preheat grill to medium-high heat (about 425°F). Grill marinated fish for 3-4 minutes per side until cooked through and slightly charred.
  4. Step 4: Break or cut 6 corn tostadas if desired. Top each tostada with pieces of grilled fish.
  5. Step 5: Spoon pickled red onions over the fish, sprinkle 1/4 cup chopped fresh cilantro, and serve with lime wedges.

Frequently asked questions

How long does Achiote-Grilled Fish Tostadas with Pickled Red Onion take to make?

Total time is about 50 minutes (40 min prep + 10 min cook). Most home cooks find this fits comfortably into a weeknight; double the batch on Sunday for two dinners.

How do I store leftover Achiote-Grilled Fish Tostadas with Pickled Red Onion?

Cool to room temperature within 2 hours, then store in an airtight container in the fridge for up to 4 days. Reheat covered in a 350°F oven for 10-12 minutes, or microwave at 70% power in 60-second bursts to keep achiote paste from drying out.

Can I substitute ingredients in Achiote-Grilled Fish Tostadas with Pickled Red Onion?

Yes — most ingredients in this recipe have flexible swaps. For oil, use any neutral high-smoke-point oil (avocado, grapeseed, refined coconut). For aromatics, dried herbs at ⅓ the volume of fresh work in a pinch. The full ingredient list is shoppable on Instacart so you can see substitutes in real time.

How do I scale Achiote-Grilled Fish Tostadas with Pickled Red Onion for a different number of people?

The recipe is written for 4 servings. Multiply each ingredient by (your serving target / 4). Cook time stays roughly the same up to 2x; for 3-4x batches, switch from a skillet to a sheet pan or stockpot so the food isn't crowded — overcrowding steams instead of browns.

What goes well with Achiote-Grilled Fish Tostadas with Pickled Red Onion?

Mexican seafood like this pair well with a simple grain (rice, couscous, or crusty bread), a quick salad with acid (lemon vinaigrette, pickled onions), and a pan sauce or yogurt-based dip. Tap "Plan a meal with the AI" to get specific side suggestions.

Related recipes