Heat a cast-iron compartment skillet over medium heat. Add bread slices and cook, turning occasionally, until lightly golden and toasted on both sides, 2 to 4 minutes. Remove from pan.
Spread 2 ounces sausage onto 1 side of each bread slice. Return to pan, sausage side down. Cook over medium heat until golden brown. Remove from heat. Wipe skillet clean.
Reduce heat to medium-low. Spray skillet with cooking spray. Crack eggs into pan. Cook, turning once, until egg whites are set and yolks are cooked to desired level of doneness, 3 to 4 minutes.
Top sausage on each bread slice with 1 egg. Sprinkle evenly with salt and pepper. Garnish with Parmesan and thyme, if desired.
Recipe by Southern Cast Iron at https://southerncastiron.com/unique-antique-compartment-skillets-griddles/