Preheat oven to 225 degrees, and set the oven rack to the middle position.

Mix cereals, nuts and sunflower seeds in a large mixing bowl.

In a measuring cup, mix together remaining ingredients until combined.

Pour the wet ingredients over the cereal, nut mixture and mix well with a spatula, to combine.

Spread the nut-Chex mixture onto a sheet pan and bake for 45-50 minutes, stirring at least twice to prevent the bottom from burning.

Let cool to room temperature and serve

Store any leftovers in an airtight container for up to two weeks.