Herbs, spices, and garlic should not come in direct contact with food that is vacuum-packed and cooked sous vide, as the flavor will be stronger in areas where there is direct contact. To avoid this, we make sachets, which allows the flavors to infuse the other ingredients evenly.
Place a piece of food-safe plastic wrap large enough to roll up the herbs, spices, and garlic on the work surface. Lay the herbs on the wrap and nestle any garlic and spices in the herbs. Roll up the sachet, and cut off the ends of the roll. Add the sachet to the sous vide bag with the other ingredients; discard after cooking.