Preheat the oven to 325 degrees F.
Prepare a baking sheet with parchment paper and nonstick spray, or line it with a silicone baking mat.
In a large bowl, combine the honey, brown sugar, garam masala, chile flakes, fennel seeds, orange bitters and kosher salt. Stir to combine. Add the mixed nuts and toss well.
Spread the nuts out evenly on the prepared baking sheet and bake for 20 to 25 minutes. Be sure to give them a toss halfway through the cook time.
When you pull the nuts out of the oven, give them a generous sprinkling of fleur de sel and then let them cool completely. Once cooled, you can break them apart and serve.