Cream the butter and sugar in the bowl of an electric mixer fitted with a paddle, on medium speed. Scrape down the bowl as necessary. Cream the mixture until it is smooth and fluffy. Add the egg yolks one at a time, mixing between each addition. Scrape down the sides of the bowl. Beat for 1 minute and add the vanilla. Add the flour and salt to the butter mixture and beat on low speed until it is fully incorporated. Increase the speed to medium and mix until the batter is thick and creamy, about 2 minutes. Scrape down the sides of the bowl and the paddle.
Generously dust a large sheet of parchment or waxed paper with the remaining 2 tablespoons of flour. Spoon the dough down the center of the paper, fold the paper tightly over the dough, and roll into a cylinder about 3 inches in diameter and 12 to 14 inches long. Refrigerate for 8 hours.
Preheat the oven to 350 degrees F.
Line a baking sheet with parchment or waxed paper. Remove the dough from the refrigerator and peel away the paper. Using a sharp knife, cut the dough crosswise into 1/2-inch thick slices. Place them 2 inches apart on a baking sheet. Generously sprinkle the top of each cookie with almonds, lightly pressing them into the dough. Bake until lightly golden, about 20 minutes.
Remove from the oven and let cool completely in the pan.
To serve: Place a couple of scoops of Fresh Lemon and Lavender Ice Cream in a cold martini glass. Place the glass on a small plate. Place a couple of cookies on the plate. Garnish with a slice of fresh lemon and a couple sprigs of lavender.
In a saucepan, combine lemon zest, lavender, milk, and cream. Bring to a boil. Steep for 20 minutes. Strain. Whisk the egg yolks and sugar together. Whisk 1 cup of the hot cream into the egg mixture. Mix thoroughly. In a steady stream, slowly add the egg mixture to the hot cream mixture. Continue to cook for 4 minutes, stirring occasionally. Remove from the heat and cool completely. Strain the mixture. Add the mixture to the electric ice cream maker. Process according to manufacturers' directions.