Heat oven to 350°. Line fifteen 2 1/2-inch muffin cups with paper baking cups.
In a large bowl, whisk together flour, poppy seeds, baking powder and salt. Set aside. In a second large bowl, beat butter and sugar on medium-high for 2 minutes, until light and fluffy. Gradually add in eggs, one at a time, until just combined. Beat in extracts, lemon juice and zest. On low, beat in flour mixture, alternating with milk, until just combined.
Evenly spoon batter into prepared muffin cups, filling each about three-fourths full. Bake at 350° for 20 to 21 minutes or until a wooden pick inserted in the center comes out clean. Remove to a wire rack and cool completely.
Fill cupcakes by placing lemon curd in a pastry bag fitted with a medium star piping tip. Press the end of the tip into each cupcake and gently press until top of cupcake starts to rise up a little.
Heat broiler. Place egg whites in a clean bowl and beat on medium-high until foamy. Beat in cream of tartar and gradually add in sugar. Beat until stiff peaks form. Frost each cupcake with meringue. Broil 6 inches from heat for about 45 seconds, until tops start to lightly brown.
Refrigerate for 1 hour before serving.