Lightly butter a baking sheet. Roll out dough on a lightly floured surface into a 12-inch square. Cut dough in half. Cut each half crosswise into 1-inch-thick strips (for 24 strips total). Tie each strip into a knot, gently stretching dough as needed. Place on prepared sheet. Loosely cover with plastic wrap; let rise in a warm place until slightly puffed, 1-1 1/2 hours.
Preheat oven to 375°. Bake knots until cooked through and golden, 25-30 minutes.
Meanwhile, heat 1/2 cup butter with garlic in a small saucepan over medium heat, stirring occasionally, until garlic is fragrant, about 3 minutes. Transfer garlic butter to a large bowl; stir in oregano.
Place warm bread knots in bowl with garlic butter; toss until well coated. Transfer to a platter. Sprinkle with flaky salt.
To scale up, double or triple the ingredients. Arrange racks in upper and lower thirds of oven. Bake knots, rotating pans halfway through (work in batches if tripling). Serve half of knots. When platter runs low, rewarm remaining knots in a 350° oven.
