Locations and Uses
Acorns are common throughout Hyrule, often found at the base of Trees or when a Tree is cut down. They can also be obtained by killing Bushy-Tailed Squirrels. When Cooked, each Acorn will add half a heart, and the first Acorn used will provide a 10 second boost to the duration of effects in Recipes. Any further Acorns added will not provide any benefits to the resultant Food or Elixir. Acorns are also used as an ingredient for Brown Dye at the Kochi Dye Shop in Hateno Village.
Acorns can be eaten raw to restore a quarter of a Heart. As Acorns are flammable, they will ignite when exposed to Fire or Scorching Temperatures. If left ablaze, Acorns will turn into Roasted Acorns.
Often found on the ground near trees. Squirrels adore this nut, so you may have competition while foraging. Add one to a meal for a nutty seasoning." — Inventory (Breath of the Wild)