Heat the oil in a large skillet over medium-high heat.
Add the shallot and garlic and saute until softened and starting to turn golden brown, about 3 minutes.
Slowly stir in the spinach, stirring. Cook until wilted and bright green, about 2 minutes.
Transfer the mixture to a mixing bowl.
Stir in the cream cheese. Let cool for 5 minutes.
Stir in the mayonnaise, salt and pepper.
Slice the eggs in half. Transfer the egg yolks to the spinach mixture and stir until smooth. You might have to add a bit more mayonnaise. You want the mixture to be just thin enough to pipe thru a piping bag or icing tool.
Transfer mixture to a piping bag or icing tool and pipe into the center of each egg.