Step #1 To make biscuits: preheat your trusty oven to 450-degrees F.
Step #2 Grease baking sheets.
Step #3 In a large bowl sift together first 5 ingredients (flour - baking soda).
Step #4 Cut in shortening until mixture resembles coarse meal.
Step #5 Stir in buttermilk until dough comes together.
Step #6 Turn dough out onto floured board & knead for about 10 times, adding more flour if dough becomes sticky.
Step #7 Roll dough out to a thickness of 3/16 inch & cut 16 rounds using a 2-inch biscuit cutter.
Step #8 Transfer to prepared sheets & bake for 12-14 mins or until lightly browned.
Step #9 Cool on wire racks.
Step #10 To make relish: In a skillet over med-heat/flame fry bacon until crisp; remove & drain on paper towels.
Step #11 Pour off all but 3 tbsps of grease.
Step #12 Stir water into skillet & then add tomatoes, simmering for 15 - 20 mins or until vegetables are soft & mixture thickens, bell peppers & garlic, stirring every once in awhile.
Step #13 Stir in parsley & season this with salt & pepper.
Step #14 Crumble in bacon.
Step #15 Set aside.
Step #16 Preheat broiler.
Step #17 Arrange oysters on broiler pan, brushing with oil & lemon juice.
Step #18 Broil for 3-5 mins or until edges begin to curl, turning once.
Step #19 BE CAREFUL - DO NOT OVERCOOK!
To assemble sandwiches: split biscuits.
Step #20 Spread both cut sides with relish.
Step #21 Top one half with oyster & cover with second half.