Truc: I never could find the word or an explanation for it in the cookbook in which I discovered it. Seem an odd editorial oversight to me, using a culinary term unknown to most and not defining it first. I checked with Merriam-Webster, Foodreference.com, a few other tried and true sources, and then gave up.
In the recipes, the word "truc" preceded helpful notes on technique or timing. Nothing so dazzling that the origin of the mysterious term held my attention for too long.
Then, I came upon an article on cooking schools and culinary vacations. We know culinary travel is here to stay. The article that caught my eye: A Cook's Tour in Provence.
Linda Danneberg describes a six day tour of the French countryside, dicing and braising along the way. "Carole is a good-humored and accessible teacher, her recipe instructions punctuated with a wealth of helpful chef's trucs (technical tricks and tips.) We are juicing lemons..." Then she goes on to share the instructor's truc for juicing a lemon: slice at about 3/4 inch down, slice the flesh of the lemon into a tic-tac-toe grid, squeeze, juice, no seeds.
Mystery solved: truc is a fancy-pants cheffie word for a trick or tip.
Though I have noted the worrisome trend of cookbooks being "dumbed down" in 75th Anniversary of Joy of Cooking, it still seems we could hope for a balance. Enough guidance to understand the terms used, without having to explain that greasing a pan means only the inside.
To learn about a unique cooking school in Ireland and a terrific book about a family adventure in food self-sufficiency read Culinary Travel Meets Slow Food. Both provide a host of trucs for traveling or homebound cooks.