Heat a large skillet over medium-high heat and add olive oil and butter. Allow the butter to melt until it bubbles.

Season the cod fillets generously with salt and pepper, then place them in the hot skillet. Cook for 2-3 minutes on each side until lightly golden.

In the same skillet, add halved cherry tomatoes, stirring them occasionally. Blister the tomatoes for about 3-5 minutes until soft and slightly charred.

Reduce heat to medium and add chopped garlic, green onion whites, and red pepper flakes. Sauté for about 1 minute until fragrant.

Pour in chicken broth (or white wine) and bring to a simmer. Stir in lemon juice and remaining butter, seasoning to taste.

Return the cooked cod to the skillet, spooning sauce over it. Sprinkle with green onion greens, parsley, and basil. Heat through.