Grease a tube or bundt pan with solid vegetable shortening then sugar (or flour. I use sugar because it doesn't leave white spots like flour does.)
Preheat oven to 350°F
In the bowl of your electric mixer, cream butter and sugar until light and fluffy.
Add eggs one at a time, beating until the yolk disappears into the batter before adding the next.
Next, add flour and buttermilk alternately, beginning and ending with the flour. Stop the mixer and scrape the sides and bottom, then mix again.
Add vanilla, lemon zest, and lemon juice. Mix to combine. Stop the mixer again and scrape the sides and bottom with a spatula. Mix again to combine.
Pour ½ of the batter into your prepared pan.
Add 2 tablespoons flour to the blueberries to toss to coat them.
Sprinkle the blueberries over the batter. Next, top with the remaining batter and smooth the top.
Bake at 350° for 90 minutes. Test for doneness with a long, thin wooden pick or cake tester. Cook another 5 to 10 minutes or more if needed. (When tested, no crumbs or dry crumbs will cling to the skewer.)
Cool on a wire rack for 30 minutes before inverting onto a serving tray. Cool the cake completely before covering or frosting.