Line a 9 x13 pan with foil, so that it hangs over the sides. Spray foil with cooking spray and set pan aside.
Heat olive oil in a large saute pan, and add quinoa and oats. Stir to coat with oil, and lightly toast the oats and quinoa for about 3 minutes. Remove from heat and let cool.
Place oat mixture into a large mixing bowl, and add cashews, sunflower seeds, chopped fruit, chocolate chips and Cheerios. Stir everything together to combine well.
Place sugar and water in a medium saucepan, stir lightly to dissolve, and bring to a boil. Cook over medium-high heat without stirring, until sugar is a faint golden color (about 6 minutes). Reduce heat to medium-low and continue to cook, stirring only as needed, until color is deep amber (another 1-3 minutes).
Immediately remove from heat, and stir in half and half, vanilla and peanut butter or PB2 powder.
Mixture will bubble vigorously, so be careful! Stir well and work quickly before caramel sets.
Quickly stir the caramel mixture into the oat/Cheerios mixture and stir well to coat everything with the caramel.
Transfer the mixture into the prepared pan and pat and pack very firmly into a smooth, flat layer. Make sure to pack the oat mixture as tightly as possible, or the bars will fall apart. Chill for at least 3 hours in the refrigerator. When chilled, lift foil out of pan, and cut into 16 bars.
Wrap each bar with wax or parchment paper as shown, as they can be a bit messy if eaten warm.
Store extras in an airtight container the refrigerator or freeze.