Whisk together flour, baking powder, psyllium husk powder, sugar, salt, and baking soda in a large bowl.
Add butter to flour mixture and use your fingers to break up butter chunks until only small, pea-sized pieces remain.
In a separate bowl, combine yogurt, egg, oil, and lemon juice.
Using a rubber spatula, thoroughly combine yogurt mixture with the flour mixture until there are no flour pockets remaining.
Cover bowl with plastic wrap and let batter rest at room temperature for 30 minutes. DO NOT SKIP THIS STEP!
Preheat oven to 450 degrees while biscuit dough is resting. Line a rimmed baking sheet with parchment paper and then set this baking sheet inside a second baking sheet. BE SURE TO USE TWO BAKING TRAYS. THIS ALLOWS THE BISCUITS TO COOK AT A HIGH TEMPERATURE WITHOUT BURNING THE BOTTOMS OF THE BISCUITS.
Using a 1/3 cup dry measuring cup that is lightly oiled (for easier scooping and releasing), scoop batter and drop onto parchment paper. Repeat with remaining batter, placing biscuits relatively close together. Recipe makes six biscuits.
Bake for 8 minutes and then rotate the pan. Continue cooking for another 5-7 minutes, until biscuits are golden brown. Total baking time is 13-15 minutes, checking biscuits after 13 minutes for doneness. Let cool for 10-15 minutes before serving.
Place biscuits in a basket or on a small platter and serve with butter, jam/jelly/preserves, honey, etc, some fresh fruit, and a mug of hot coffee!!