1 Chop the almonds: Place the slivered almonds in a food processor. Pulse until the almonds are broken down into smaller bits, about 1/4 inch in size. They should be the size of the chopped nuts you would sprinkle over an ice cream sundae.
If you don’t have a food processor, you can chop the nuts by hand or place them in a ziplock bag and crush them with a wooden rolling pin until they are the right size.
2 Add the flour and cocoa powder to the food processor bowl. Pulse a couple of times to blend together.
3 Make the cookie "batter" on the stovetop: In a medium-sized saucepan, place the sugar, butter, cream, and honey. Heat until the sugar is dissolved and the butter has melted. Remove from heat and stir in the vanilla extract.
Add the dry almond mixture and stir until incorporated. Set aside to cool for 20 minutes.
4 Preheat the oven to 325ºF. Line a baking sheet with parchment paper or a silicon baking mat.
5 Spoon out the cookies: Once the batter has cooled (it will still be warm), use a teaspoon measure to spoon out the cookies onto the prepared baking sheet (1 teaspoon per cookie). Space the cookies about 3 inches apart; they will spread a lot during baking. (On a 12 x 18 sheet, I found 6 cookies fit comfortably.)
6 Flatten the cookies: Dip your finger in some water, then use it to spread the batter into a round circle, with the nuts in a single layer on the pan. This will encourage the batter to spread evenly in a circle.
7 Bake the cookies: Bake the cookies in the oven for 6 to 8 minutes. If you are using parchment paper, the cookies will bake faster. If you are using a silicon baking sheet, the silicon insulates the heat and it takes a little long to bake (but they will bake more evenly).
Remove the pan from the oven once the edges of the cookies start to darken and brown and transfer to a cooling rack. Be careful as the cookies go from done to burnt fairly fast.
While the cookies are still warm from the oven, take a look at them and see if any of them are not quite round. If they are not as nicely shaped as you would like, use a spatula to carefully nudge the sides of the cookie into a round circle. You will have to work fairly quickly as the cookies firm up as they cool.
8 Cool the cookies: Let the cookies cool on the pan for 10 to 20 minutes, until they are set. It's fine if they're still a little soft, but they should be able to be transferred in one piece without tearing or creating ripples in the cookie.
It helps to use a very thin, flat spatula so you can easily slide under each cookie. Also, if you have a wire rack that has crisscross wires, this is ideal for cookies like this since any under-baked cookie will slump a little bit on racks with more widely-spaced wires. Let the cookies cool completely.
9 Continue baking the cookies in batches until all the batter has been used.
10 Sandwich the cookies with chocolate: Once the cookies have all been baked and cooled, melt dark chocolate by placing it in a microwave-safe bowl and cooking it in 30 second increments, stirring between each increment. (You can also melt the chocolate on a double boiler, if you prefer.)
Once the chocolate has melted, pick two cookies that are roughly the same size and smear a thin layer of chocolate on the bottom of one of them. Place the matching cookie bottom on top and set the cookie sandwich on a baking sheet lined with parchment paper or a wire rack.
Repeat with the remaining cookies. Drizzle any remaining chocolate over the Florentines.
11 Wait for the chocolate to firm up and harden before serving or packaging. Stored in an airtight container, these cookies will keep at room temperature for 3 days, or in the fridge for about 2 weeks.