You don't need a book for tarts.
Once you learn how to make a short crust and a custard (pastry cream, frangipane, flan, mousse, quiche, etc.) you can make any tart, or make up your own.
Becoming a better baker is learning the fundamentals (science) of baking, not blindly following a recipe book like Tartine.
Advanced Bread and Pastry textbook on science of baking by San Francisco Baking Institute
How Baking Works (not a recipe book, but a textbook on the function of ingredients)
Culinary Institute of Americas Mastering The Art and Craft Baking and Pastry, it's crap for the science but as textbook it has just about every formula a professional baker will learn to make in a pastry program. Anyone using this book will need to know baker‘s percentages because they’re not recipes, they are formula, and scaled for production.