How to Make It
Heat oven to 350° F. Place the flour, sugar, salt, baking soda, and butter in the bowl of a food processor and pulse several times until the ingredients are combined and a crumbly dough is formed. Add the oats and lemon zest. Pulse quickly twice to combine.
Press 2/3 of the dough firmly into a greased 9-by-13-inch pan. Spread the jam evenly over the crust. Sprinkle the remaining dough over the jam, gently pressing down.
Bake until golden brown, about 20 minutes. Cool completely, about 2 hours. Cut into 24 bars. Store in airtight containers