Preheat the oven to 350 degrees F. Cover 2 baking sheets with parchment paper or silpat mats.
Place the oats in a blender or food processor and process until finely ground. In a medium bowl, whisk together the ground oats, flour, baking soda, and salt.
In a large bowl, use an electric mixer to combine the butter, cream cheese, sugars, vanilla and lemon juice. Add the dry ingredients and continue to mix until all is well-combined. Stir in the chips or M&M's.
Spoon dough in rounded tablespoonfuls onto the baking sheets, leaving about 1½ inches between each cookie.
Bake until cookies are lightly browned, 16 to 18 minutes. Transfer to wire rack to cool completely. Store in a sealed container to keep them soft and chewy.
Notes
If you do not want to grind oats for this recipe, go ahead and use regular oats. Just make sure that you are using quick cooking oats.