Bring the brown sugar, honey, peanut butter and butter to a boil in a medium saucepan. Stir constantly.
Remove from heat after reaching a boil.
Stir in vanilla extract and cereal or granola.
Add in optional almonds and M&M candies.
Press into an aluminum foil lined pan.
Place the pan in the refrigerator until solidified enough to cut into bars.
Store your homemade no-bake granola bars in the fridge and enjoy!