Preheat the oven to 350 F. Set a rack in the lower third of the oven. Spray 10-inch Bundt panwith non-stick flour spray.
Sift together the flour, Clabber Girl Baking Powder, baking soda and salt. Set aside.
Using a stand mixer or hand held beaters, cream the butter and honey for 3 minutes. Add the beaten egg very slowly to incorporate. Stop and scrape the bowl a few times. Add the vanilla.
Set the speed on low and alternately add the flour mixture in three parts and the milk in two parts, beginning and ending with the flour. Stop and scrape the bowl in between additions to assure it is evenly mixed, increasing the speed briefly after each addition until smooth and creamy. Increase the speed at the end for about 30 seconds.
Fold in the lemon zest and poppy seeds. Spread the batter evenly in the prepared pan and smooth the top. Bake for about one hour or until a wire cake tester pressed in the center comes out clean.
Allow the cake to cool for about 15 to 20 minutes and invert from the pan to finish cooling on a wire rack.
For the glaze--While the cake is baking, whisk together the lemon juice and honey. Set the rack above a plate and brush on the glaze while the cake is still hot. Brush or pour any glaze that runs onto the plate back onto the cake. Cool and serve at room temperature. If you like, sift powdered sugar over the cake once it is completely cool.