Preheat oven to 350 F/ 177 C. Grease a 13 x 9 pan.
Run nuts through food processor until roughly chopped. Add oats and pulse it a few more times until nuts and oats are coarsely chopped. Set aside.
Cream butter and sugar together, then add eggs and beat well. Add salt and flour, cup by cup, until well mixed. Add nut and oat mixture, and beat until combined.
Put aside 3 cups of the dough, then press the remaining dough into your prepared 13 x 9 pan. Spread the jam on top, staying about 1/2" from the edges, then crumble up the saved dough and sprinkle it on top.
Bake in a 350 F/ 177 C oven for about 40 minutes, until topping is between golden and toasty brown. Allow the cookies to cool completely before cutting.
Notes
For dairy free, substitute a vegan buttery spread in place of the butter.For gluten free, substitute a one-to-one GF baking flour in place of the all purpose flour and be sure you use certified GF oats.NOTE: I wrote this recipe down years ago and have since lost the original source, and could not find it upon searching. So, unfortunately, I cannot credit where the recipe comes from.