It's mostly oats and pecans.
Of course, there may be some brown sugar, butter, molasses...All the things that make a brittle, brittle.
I inspected the floor. Don't get any on the floor. I didn't get any on the floor.
Recipe: Pecan Brittle
1 1/4 cup old-fashioned oats
1 cup pecans
3 tablespoons unsalted butter
1/2 cup dark brown sugar
3/4 teaspoon cinnamon
3 tablespoons light corn syrup
1 tablespoon molasses
1/2 teaspoon kosher salt
Toast oats and pecans in a non-stick pan over a low flame until things turn a nice golden (a few minutes—give or take a minute, depending on your flame). Transfer to a bowl.
Add butter, brown sugar, cinnamon, light corn syrup, molasses, and salt to same non-stick pan. Same low flame. Stir with rubber spatula until things bubble (a few minutes—give or take a minute, depending on your flame).
Add wet to dry. Stir until coated.
Transfer to plastic wrap lined pan. I used a 9x9 square. Chill in refrigerator for 30 minutes before slicing/breaking and eating.