Have ingredients at room temperature. Position rack in lower third of oven; preheat to 325°F. Grease and flour a 6-well bundtlette pan.

To make cakes, over a sheet of waxed paper, sift together flour, baking powder and salt. In the bowl of an electric mixer fitted with the flat beater, beat butter on medium speed until creamy and smooth, 1-2 min. Add sugar and beat until light and fluffy; stop mixer occasionally and scrape bowl. Gradually add eggs, beating well after each addition. Beat in lemon oil. Reduce speed to low; add flour mixture in three additions, blending each addition until just incorporated. Stop mixer occasionally and scrape bowl.

Spoon batter into prepared pan; spread evenly. Bake until a toothpick inserted into cakes comes out clean, about 20 min. Transfer to a wire rack; cool 10 min. Tap pan on work surface, set rack over waxed paper and invert cakes onto rack.

To make glaze, split vanilla bean lengthwise; scrape seeds into a small saucepan. Add water, sugar, honey and butter. Heat over low heat just until sugar dissolves. Increase heat to medium and cook 5 min. Remove from heat; cool 10 min.

Brush warm cakes with glaze. Cool completely before serving.