In a large, heavy skillet on medium heat, drizzle bread with 1-2 tablespoons of olive oil and toast until lightly charred, about 3 minutes on each side. Set aside. Wipe skillet clean and return to stovetop on low heat, add butter and allow to fully melt while swirling around the pan to cover the surface area. Once the butter has melted, turn the heat to medium, add garlic and sauté until starting to soften, then add mushrooms and allow to cook without stirring for 3 minutes, toss and do the same on the other side. Add in vinegar, walnut, salt and pepper to taste and remove from heat.
In a small nonstick skillet, drizzle a little olive oil and fry eggs one at a time to the desired doneness. Divide ricotta between the two slices of toast. Spoon over sautéed mushrooms and their cooking liquid and top each with a fried egg. Drizzle more olive oil over eggs and garnish with freshly torn herbs.