For the blinis:
Preheat a griddle to 350 degrees or set a griddle or large, heavy skillet over medium-high heat.
Stir the yeast into the water in a small bowl. Let stand until foamy, about 5 minutes.
In a medium bowl, stir together the flours and salt. Add the milk, yeast mixture, and butter, whisking to combine after each addition. Let the mixture sit at room temperature for about 10 minutes.
Coat the preheated griddle or skillet with cooking spray. Use 1 tablespoon of batter per blini and cook for 2-3 minutes on each side, until crisp around the edges and golden brown. Set aside and keep warm.
For the crema:
Pulse the avocado in a food processor until smooth. Add the mayonnaise, yogurt, lemon juice, Tabasco, and salt and process until smooth. Spoon into a squeeze bottle* and refrigerate until ready to use. The crema can be made one day in advance.
In a small bowl, break the crabmeat into small chunks and stir in the lime juice to coat.
Squeeze about ¼ teaspoon of crema on each blini and top with about 1 teaspoon of the crabmeat mixture. Spoon about 1 teaspoon of pico de gallo on top of the crabmeat and top it off with an artful squiggle of crema. Serve immediately.
*Note: If you don’t have a squeeze bottle on hand to dispense the crema, use a small sandwich-sized plastic bag. Fill it no more than two-thirds full and snip a tiny bit off the bag’s corner with sharp scissors. Squeeze lightly to push the desired amount of crema onto the blinis.