Remove mahi mahi fillets from the refrigerator and let them rest at room temperature for about 15-20 minutes.

Pat the fillets dry with paper towels, season with salt and pepper, and lightly dredge in flour.

In a skillet, heat olive oil and butter over medium-high heat until shimmering.

Add the seasoned mahi mahi fillets to the hot skillet and cook for about 4 minutes until golden, then flip and cook for an additional 2-4 minutes.

Remove the fillets and tent with aluminum foil to keep warm.

In the same skillet, sauté minced shallots and garlic until fragrant.

Whisk in chicken broth, thyme, parsley, and lemon juice. Simmer for about 3-4 minutes.

Stir in heavy cream and cornstarch, whisk until combined, and simmer until thickened.

Return mahi mahi to the skillet to coat with sauce, heating for just a minute.

Plate the mahi mahi fillets and drizzle with additional sauce before serving.