Boil the spaghetti in a large pot, according to box instructions. Drain and set aside.
While the spaghetti is boiling, chop the onions and bell pepper and mince the garlic.
Lightly season the shrimp and scallops with Creole seasoning. Then heat the oil over medium heat in a heavy-bottomed skillet.
Add the shrimp and scallops (together or separately, it's up to you) and sauté for 3-5 minutes or until the shrimp turns pink and begins to curl.
Remove the shrimp and scallops from the pan and transfer them to a plate.
Add about 2 tablespoons of butter to the skillet, followed by onions, garlic, thyme, and bell pepper. Sauté the ingredients for 3-4 minutes, stirring occasionally to prevent burning.
Next, pour the chicken stock, diced tomatoes, and lemon juice in. Stir until combined. Cook for about a minute, and then season with salt, pepper, and Creole seasoning. Optionally, add some red pepper flakes too!
Add the drained pasta to the skillet and mix it with the sauce.
Next, return the shrimp and scallops to the skillet and mix gently to combine all ingredients thoroughly. Adjust the seasonings to taste.
Finally, turn off the heat and let it soak up some of the sauce for a few minutes.
Serve warm and garnish with a lemon wedge and pepper flakes if you like it spicy.