Mix the oats, nuts, brown sugar and spices in a large bowl.
In a sauce pan add the maple syrup and butter and heat gently, until butter melts. Pour the mixture over the oat mixture and toss to mix well.
Spread mixture in a buttered 10 x 15-inch baking pan. Bake until golden brown, about 20-30 minutes. Set timer every 10 minutes to stir granola for even browning. Let cool in pan. Store in airtight container.