Whisk in sugar, water, salt, cumin, cayenne, garlic and ancho powders. Toss nuts in mixture until well coated.
Spray a sheet pan with nonstick cooking spray or line with parchment.
Spread nuts out on the prepared pan in a single layer. Cook for 45 minutes until slightly golden, turning nuts with a spatula every 15 minutes so they toast evenly and don't stick.
Set the nuts aside, stirring periodically as they cool. When completely cool, transfer to serving bowl and garnish with dried red chiles if desired.
