In the bowl of a stand mixer, whisk together milk, sugar, 3 tsp. cardamom, and yeast; let sit until foamy, about 10 minutes. With dough hook attached, add eggs one at a time; mix to combine.
Add flour and salt; mix until a dough forms. Knead dough on medium speed for 2 minutes. While kneading, slowly add butter a little at a time, mixing until incorporated before adding next batch, 3–4 minutes; continue kneading for 4 minutes more after last of butter is added.
Transfer dough to a greased bowl and cover with plastic wrap; let sit until doubled in size, about 1 hour. Punch down dough; cover again with plastic wrap and let sit until fully risen, 30 minutes.
Heat oven to 375°.
Transfer dough to a work surface and divide into 2 equal pieces. Set 1 piece aside and divide other piece into 3 equal portions. Roll each portion between your palms and work surface to create a 16" rope. Braid ropes together to form a loaf.
Transfer loaf to a parchment paper–lined baking sheet. Repeat with second dough piece. Cover loaves with plastic wrap and let sit until slightly puffed up, about 20 minutes. Or you can make one large wreath like I did with all the dough.
Whisk together remaining cardamom, cream, and egg yolk in a small bowl; brush over loaves.
Sprinkle with sugar and almonds (if using); bake, one loaf at a time ( *or bake one large wreath) until golden brown, 20–25 minutes.
Transfer to a rack; let cool 10 minutes before serving.