Sprinkle 1 tablespoon of salt in the bottom of a dish large enough to hold the duck legs in a single layer.
Add layer with half the garlic, shallots, and thyme in the container. Arrange the duck, skin-side up, over the salt mixture, then sprinkle with the remaining salt, garlic, shallots, and thyme and a little pepper. Cover and refrigerate overnight.
Melt the duck fat in a saucepan. Brush the salt and seasonings off the duck. Arrange the duck pieces in a single snug layer in a high-sided bakingdish or ovenproof saucepan. Pour the melted fat over the duck being sure to cover and place the confit in the oven.
Cook the slowly at low temperature with just a bit of bubbling until the duck is tender and can be easily pulled from the bone, about 1 hour.
Remove from the oven. Cool and store the duck in the fat. It will keep in the refrigerator for several weeks.