Preheat oven to 400 degrees F. Beat cream cheese, egg and natural sweetener in a large mixing bowl until smooth. Stir in vanilla and salt. Fold in rhubarb. Pour rhubarb mixture into casserole dish.

To make the biscuits, place the whites into a bowl or stand mixer and whip egg whites until very fluffy and stiff. In a separate medium bowl, mix the baking powder into the almond flour. Then cut in the butter and salt (if the butter isn't chilled, the biscuits don't turn out). Gently fold in the dry mixture into the whites. Form into 2 inch round biscuits making sure the butter stays in separate clumps.

Place the biscuits onto the rhubarb mixture in the casserole dish.

Bake for 12-15 minutes.