• Preheat the oven to 350°F (180°C). Line a baking sheet with parchment paper.
• Soak the saffron in the white wine for 15 to 30 minutes to extract all the flavor and color.
• Meanwhile, arrange the baguette slices on the baking sheet. Bake for 4 to 6 minutes, until golden brown and crispy. Let cool.
• Heat 1 tablespoon of olive oil in a medium pot over medium heat and sweat the leek, shallot, and fennel for 2 minutes, until they start to soften. Add the garlic and cook for another minute. Add the potatoes and stir briefly before deglazing the pan with the saffron-infused white wine. Add the tomatoes, lower the heat, pour in the stock, and simmer for 10 minutes.
• Add the monkfish and parsley. Chop 1 of the dill sprigs and sprinkle it over the stew. Cover and cook for 4 to 6 minutes, then check to see if the potatoes are tender by inserting the tip of a knife; if it slides in easily, the potatoes are done.
• Garnish the stew with the remaining dill sprig and serve with croutons and rouille.

Rouille:

• Mash the bread with the garlic and saffron in a mortar to form a smooth paste. Add the cayenne pepper and whisk in the egg yolk. Slowly add the olive oil, stirring constantly. Keep whisking until the texture is similar to that of mayonnaise. Season with lemon juice and salt.