Blanquette de veau, a rich veal stew with a silky white sauce, really marks my entry into France. I first made it at Anne Willan’s cooking school, La Varenne, when I interned there to be closer to Kendall’s new life. Though I’d cooked French food for years, I wanted to hone my skills in a different setting, too. I learned how the stew relies on onions, mushrooms, and tender veal shoulder, but, in a break