Yes, mandelbrot is exactly like biscotti. Mandelbrot is translated as almond bread in German and Yiddish, and is baked twice just like biscotti. My wife bakes biscotti with slivered almonds. I suggest that you Google for recipes using the key words mandelbrot and biscotti, but one at a time.
Our family's mandelbroit is very crunchy (a bit crumbly, even). It doesn't have cinammon, but you could add some to your liking. My grandmother made a dryer mandelbroit with more of a "crumb", and the family liked this recipe, while her cousins made this richer crumblier one. We liked theirs so much more that we ditched tradition and switched :)
1/2 cup oil
3 cup sifted flour
3 tsp baking powder
2 tsp vanilla, or 1 tsp vanilla and 1 tsp almond extract
1 1/2 cups sugar
1/2 cup to 1 cup walnuts or almonds, chopped
Preheat oven to 350°. Grease bottom of cookie sheet.
Mix sifted flour and baking powder. Mix eggs and sugar, beat well, and add oil & vanilla. Mix well again. Then add flour, baking powder, and nuts. Form into 2 or 3 rolls, with oiled hands. Place on greased cookie sheets and bake 30-45 min. Cool slightly. Slice, turn on side, return to oven to toast for 5-10 minutes per side.