Mushroom-Spinach Eggs Benedict

For sauce, stir together sour cream, milk, and mustard in a small bowl; set aside.

Heat oil in a large nonstick skillet over medium-high heat. Add mushrooms and shallot. Cook for 4 minutes or until mushrooms are golden brown, stirring frequently. Stir in spinach until it just starts to wilt. Set aside.

Fill a medium nonstick skillet halfway with water. Bring water to boiling; reduce heat to simmering (bubbles should begin to break the surface of the water). Break one of the eggs into a small dish. Carefully slide egg into simmering water, holding the lip of the dish as close to the water as possible. Repeat with the remaining egg, allowing each egg an equal amount of space. Simmer, uncovered, for 3 to 5 minutes or until egg whites are completely set and yolks being to thicken but are not hard. Remove eggs from skillet with a slotted spoon.

Meanwhile, toast the two muffin halves in a toaster. Place each half on a serving plate. Top evenly with mushroom mixture; place eggs on top of mushroom mixture. Spoon sauce over eggs. Sprinkle with freshly ground pepper and nutmeg. If desired, garnish with thyme sprigs.