Make a flavorful stock. If you have fish bones make a seafood broth. Otherwise, you can use chicken or vegetable broth. If you don't have the ingredients or time, buy a pre-made broth.
Heat olive oil in a large pot. Saute onion and garlic over medium high heat until translucent. Add the potatoes, and brown slightly. Then sear the fish, scallops, and shrimp, but, don't cook them through. You just want a little color. Remove the seafood items. Set them aside to add later in the cooking process.
Add the saffron and stir well. Then add the brandy and flame off the alcohol. Add the wine when the flames die down and cook down until about half the volume of wine is left. Add in the stock and bring to a boil. The potatoes should become cooked, but not mush,
In a separate pan, melt the butter and stir in the flour to make a roux. cook for a minute over low to medium heat to cook the flour. Try not to brown too much as this is going into a lighter seafood stew, not a heavy dish. Whisk this into the boiling liquid. It will thicken slightly.
Add in the seafood, tomato, and peppers. Cover the pot to allow the mussels to open fully. This means they are cooked. Season the stew with salt and pepper. Add in the herbs and serve hot.
