1. Preheat oven to 400 degrees Fahrenheit (200 degrees Celsius).
2. Combine the oats and soy milk in a small bowl. Let sit for 10 minutes.
3. In a large bowl, whisk together the flour, cinnamon, baking soda, baking powder, and salt. Make a well in the center. Add the oat mixture, followed by the applesauce, eggs, oil, honey, maple syrup, and vanilla. Mix just until combined. (This is the key to fluffy muffins — not overmixing.) Fold in the diced apple.
4. Spoon the mixture into a muffin pan lined with paper liners.
5. Mix together crunch ingredients in a small bowl and sprinkle over the top of each muffin.
6. Place the muffin pan in the oven and bake for five minutes (this aerates the muffin). Reduce oven temperature to 350 degrees Fahrenheit (175 degrees Celsius) and bake an additional 15 minutes.
