In small bowl, place wild rice, cover with water, and let soak for at least 4 hours.
Drain rice and place in pan with 2 1/2 cups water and a couple pinches of salt. Bring to a boil, reduce heat to medium-low, and simmer, covered, until grains are very tender and some have burst open, about 30 minutes. Drain any excess liquid.
Stir together rice, sausage, cranberries, green onions, cider vinegar, and thyme.
Slice off stems from chard leaves and fillet off any thick ribs running on the backside of the leaves. Place two chard leaves side by side so there is about 25 percent overlap. Scoop about 1 cup rice mixture onto bottom third of leaves and roll up burrito-style, tucking in sides as you go. Repeat with remaining leaves and rice stuffing.
In large skillet, place chard rolls and pour in broth. Bring to a simmer and heat, covered, for 5 minutes.
Into blender container, pour 3/4 cup broth from skillet and add walnuts, maple syrup, and lemon zest; blend until smooth.
Serve chard rolls topped with walnut sauce.
Per serving: 358 calories; 19 g protein; 15 g total fat (2 g sat. fat); 44 g total carbohydrates (23 g sugars, 7 g fiber); 441 mg sodium