I like Averbakh's Comprehensive Chess Endings. It's a good volume set that helps you stay on a theme's topic.
Understanding Chess Endings by Nunn is a great place to start, then his Nunn's Chess Endings Volumes. Dvoretsky's Endgame Manual is great, and an excellent capstone I think is Encyclopedia of Chess Endings, where you already understand the hows and whys of various themes (such as the best place for a king in queen and pawn on the seventh vs. queen, how to force a win or draw from specific pawn placements, Lucena, short side defense, pantsing the bishop, that bishops are typically stronger against a knight in an endgame especially with pawns on both sides, when to achieve a pawn breakthrough, etc.) but want further drilling of and study of concrete examples. After understanding comes chunking, or improving our endgame pattern memory banks for greater confidence and intuition.
pantsing the bishop?
When did we start derobing our poor chess pieces?
It's a term from Dvoretsky's Endgame Manual. It's actually quite intuitive once the position is there.
I have one sitting on my shelf I have not read but heard a strong player years ago that loved it.
Domination in 2545 Endgame Studies by Kasparyan