Lightly oil a skillet and heat over medium heat.

Whisk eggs, half-and-half, pumpkin purée, cinnamon, vanilla, and pumpkin pie spice together in a bowl; stir in walnuts.

Dip 1 bread slice into pumpkin mixture; soak. Add soaked bread slices to the hot skillet, in batches. Repeat with remaining bread slices, stirring pumpkin mixture to redistribute walnuts as necessary.

Cook batches until golden brown, about 3 minutes per side. Serve warm.