Nameko mushrooms grow in crowded clusters of small to medium-sized caps attached to slender, straight stems. Each cap averages 2 to 8 centimeters in diameter and the stems 5 to 7 centimeters in length, and the smooth, rounded caps showcase amber, chestnut brown, to orange-brown hues. The caps are also coated in natural substances that give the surface a glossy, slippery, and somewhat viscous feel.

Nameko mushrooms have an earthy, nutty, and woodsy flavor suited for cooked preparations. The mushrooms cannot be consumed raw and can cause extreme indigestion if eaten fresh. It is also important to note that the slimy coating on the mushrooms should be left intact to thicken dishes. If dirt needs to be removed from the caps, try gently wiping or briefly running under cold water to remove the particles. The longer the mushrooms are left in water, the more their slippery coating will be removed. Nameko mushrooms are popularly blanched, sauteed, or grilled, and they can be cooked and mixed into rice porridge, combined with miso butter and whipped tofu on toast, or added to noodle dishes for texture and flavor. The mushrooms can also be served with fried tofu, used as a thickener in soups, stews, and sauces, or roasted or grilled and used as an accompaniment to meat main dishes. In Japan, Nameko mushrooms are added to nabemono, a one-pot stew, served with steamed rice, wrapped in sushi rolls, mixed into stir-fries, or combined with daikon radish and ponzu sauce as a side dish.

Nameko mushrooms are a source of potassium to balance fluid levels within the body, fiber to regulate the digestive tract, and magnesium to control optimal nerve functioning. The mushrooms also provide vitamin D to assist with calcium absorption, copper to develop connective tissues, and other nutrients, including iron, B vitamins, and phosphorus. The slippery coating on Nameko mushrooms is created from the presence of a natural layer of mucin and pectin. This layer protects the mushrooms from cold weather and drying out, and pectin is believed to help coat the mucous membranes in our bodies. Pectin is also thought to reduce to amount of sugar and cholesterol absorption, and in Japan, the slimy consistency is viewed as nourishing.