Toss the asparagus with the oil and some salt and pepper, and spread evenly on a sheet tray. Roast until slightly softened but still green and crisp, about 8 minutes.
Preheat the broiler with a rack set on the middle shelf. Heat a griddle over medium heat.
Spread one side of each slice of the brioche with butter and place butter-side down on the hot griddle. Top each slice with equal amounts of cheese, asparagus and sun-dried tomatoes. Cook until the bread is golden brown, about 2 minutes. Transfer to a baking sheet.
Fill a 10-inch skillet with water, and add 1 teaspoon salt and the white vinegar. Bring to a simmer. Crack the eggs one at a time into small ramekins, turn off the heat and add each egg to the water. Cover, and sit until the whites turn solid, 3 minutes. Gently remove with a slotted spoon.
While the eggs are poaching, cover each sandwich with the Funky Mornay Sauce and place under the broiler until the sauce is bubbling and browned in spots. Place a poached egg on each sandwich. Season with cracked black pepper and garnish with additional sun-dried tomatoes.
Funky Mornay Sauce:
In a high-sided skillet over medium heat, melt the butter. Add the flour and whisk until blonde, 2 to 3 minutes. Slowly whisk in the milk until combined. Add in some nutmeg, and simmer until thick, about 10 minutes. Whisk in the Roquefort until mostly smooth, and season with salt and black pepper.