I found this recipe browsing reddit. I really like simple recipes and this one definitely qualifies. It has a real puttanesca vibe with the oregano and capers.
1 tbsp olive oil
1 Large onion, diced
1 can diced tomatoes with oregano and basil (or add your own herbs)
4 boneless, skinless fish fillets - cod, tilapia, or other flaky white fish about 6-8g each
2 tbsp capers, drained
salt and pepper, to taste
Preheat oven to 375 degrees.
In a large, oven proof pan, heat olive oil until shimmery on medium high.
Add in diced onion, cook about 8 minutes, until soft and slightly browned.
Add diced tomatoes, herbs (if you aren't using herbed diced tomatoes add some basil and oregano- about 2 tsp each), and capers. Stir around and let reduce slightly, about five minutes.
Add fish to pan.
Pop in oven and bake about 15 minutes- until fish is flaky and white. This cooking time depends on the size of your filets and your oven- check after 8 minutes, and then again after 12.