In a large bowl, whisk together the all-purpose flour, the Redpath® Golden Yellow Sugar, finely chopped peanuts, oat flour, baking powder, baking soda, and salt until thoroughly combined.
In a separate bowl, whisk together the oat milk and apple cider vinegar. Let sit for 5 minutes or until slightly thickened. Whisk in the peanut butter, canola oil, flax egg, and vanilla extract until well mixed.
Make a well in the center of the dry ingredients and pour the wet ingredients into the well. With a large rubber spatula, gently fold the wet ingredients together with the dry ingredients until no flour streaks remain; do not overmix as this will yield muffins that are dense and chewy. Let sit for 10 to 15 minutes to allow the flour to hydrate and any gluten formed to relax.
With a trigger-style ice cream scoop or a small ladle, fill the liners halfway with batter. Place approximately 2 teaspoons (12 grams) of peanut butter into each well. Add approximately 2 teaspoons (13 grams / 10 ml) jam on top of the peanut butter. Cover the peanut butter and jam with more batter; the liners will be completely filled.
Sprinkle the tops generously with the peanut streusel topping; squeeze the streusel together for larger clumps. Gently pat the streusel onto the tops to adhere. Place muffins into the preheated oven. Bake for 10 minutes. Reduce the oven temperature to 350°F (177°C) and bake for an additional 12 to 15 minutes or until tops are golden brown, and when gently pressed, the tops spring back (see Chef’s Tips).
Remove from oven and place onto a wire cooling rack to cool; 5 minutes.
With a small offset spatula, gently lift each muffin out and place onto the wire cooling rack to cool completely.
If planning to eat within 3 days, store completely cooled muffins at room temperature in an airtight container lined with paper towels to absorb moisture. If not, store in a single layer in an airtight container or in a large freezer bag in the freezer for up to 3 months.