In the work bowl of a food processor, combine flour, salt, sugar, and poppy seeds. Pulse to combine. Add butter, and pulse until mixture is crumbly. With processor running, add half-and-half in a slow, steady stream just until dough comes together. Turn out dough, and shape into a disk. Wrap in plastic wrap, and refrigerate for at least 1 hour.
Preheat oven to 375°. Divide dough in half. On a silicone baking mat or sheet of parchment, roll one half of dough into a 15-inch rectangle. (Roll out dough as thinly as possible.) Using a pizza cutter, cut dough into 2- or 3-inch squares. Repeat with remaining dough.
Transfer silicone mats to baking sheets, and bake until crackers are crisp and golden brown, 12 to 15 minutes.
Recipe by Southern Lady Magazine at https://southernladymagazine.com/smoked-trout-dip-recipe/