Preheat oven to 400°F.
For the Filling: In an oven-safe, deep skillet, mix together sugar and cornstarch. Add the rhubarb and strawberries, mixing until coated. Add a pinch of salt, maple syrup & mix well.
Place the skillet on the stove top over medium heat, and bring to a simmer. If necessary, reduce heat slightly to maintain simmer. Let fruit cook until glossy and thickened, stirring as needed, about 10 minutes.
For the Biscuits: In a large mixing bowl, add flour and Earth Balance. Using a pastry blender, cut margarine into the flour in pea-sized pieces.
Gently stir in sugar, baking soda, and salt. Add vanilla. Gradually add ice water, a tablespoon at a time, mixing until dough comes together.
Shape the dough into a log, and break into 8 to 10 pieces. Form small, flat biscuits and place them evenly over the top of the bubbling fruit.
Transfer skillet to the preheated oven. If you do not have an oven-safe skillet, cast iron pot, or pan, transfer your filling into a 9x13 pan, placing the biscuits on top.
Bake for 20 to 30 minutes, or until center is firm and biscuits are golden. Let it cool & thicken before serving, then enjoy!