Position the racks in the upper and lower third of the oven. Preheat the oven to 375 degrees F. Line two large baking sheets with parchment paper.
Combine the oats, peanuts, strawberries, pepitas, flour, baking soda and salt in a medium bowl and mix well. In a stand mixer fitted with the paddle attachment, beat the peanut butter with the sugar until smooth. Beat in the eggs one at a time. Beat in the vanilla.
With the machine on low speed, gradually add the dry ingredients and mix until incorporated. Turn the machine off and add the strawberry preserves all at once. Mix on low speed just until the preserves are swirled into the dough, about 5 seconds; do not over mix.
Scoop the dough onto the prepared baking sheets with a 3-tablespoon cookie scoop, making 20 cookies and leaving 2 inches between each. Press down on the cookies with a fork to flatten them slightly.
Bake until the cookies are slightly risen and very lightly browned on the edges, 13 to 15 minutes; rotate the baking sheets halfway through baking. Let cool before serving.
Look for dried organic strawberries with no added sugar. If you can't find dried strawberries, you can use dried apricots, cranberries or cherries or raisins.