Over medium heat, melt 2 tablespoons of the butter together with the oil in a cast iron or stainless steel skillet
Seasoned the scallops and add to the pan and let cook on one side for 3-4 minutes until they get brown and golden. If the scallops stick to the pan they aren’t ready to turn yet, so wait another minute.
Flip the scallops over and let cook for another 3-4 minutes on the other side until browned.
Remove the scallops and set aside on a plate.
Melt the remaining 2 tablespoons of butter in the skillet and add the onions, stirring often until softened.
Then add garlic and stir for a minute longer.
Afterwards, pour in the wine to deglaze the pan. Let the wine cook down until reduced by about half (aprrox. 2 minutes) then pour in the chicken broth and bring to a simmer.
Mix the cornstarch/tapioca flour and water together and pour into the simmering sauce. Whisk and bring back to a simmer for about 5-8 minutes until the sauce is reduced and thickened.
Add in the spinach and the sun dried tomatoes with 2 tablespoons of the oil from the jar. Cook until spinach is wilted and season with salt and pepper to taste.
Place the scallops back into the sauce, cover and turn off the heat.
Cook the spaghetti according to the package directions, drain and add to the pan with the sauce.
Toss everything together in pan and serve.