Mix the cream cheese, cottage cheese and confectioners' sugar in a medium bowl.
Spread 2 waffles with the jam, then top with the cream cheese mixture; cover with the remaining 2 waffles.
Melt the butter in a large skillet over medium-high heat.
Add the sandwiches and cook until golden and crisp, about 3 minutes per side, adding more butter to the pan if needed. (Adjust the heat if the waffles are browning too quickly.)