Maple Crunch Layer Cake

Grease sides of two 9-inch (round metal cake pans; line bottoms with parchment or waxed paper. Set aside.

In large bowl, beat butter with sugar until light; beat in eggs, 1 at a time. Beat in maple extract. In separate bowl, whisk together flour, baking powder, baking soda, ginger and salt. Stir into butter mixture alternately with buttermilk and maple syrup, making 3 additions of dry ingredients and 2 of liquids. Divide between prepared pans; smooth tops.

Bake in centre of 350°F oven until cake tester inserted in centre comes out clean, about 30 minutes. Let cool in pans on rack for 10 minutes. Turn out onto rack and peel off paper; let cool completely. (Make-ahead: Wrap and store for up to 24 hours or overwrap in heavy-duty foil and freeze for up to 2 weeks.)

Candied Walnuts: Line rimmed baking sheet with foil; set aside.

In microwaveable bowl, microwave maple syrup, butter, 2 tbsp water and salt on high for 30 seconds or until butter is melted; whisk to combine. Add walnuts and toss to coat; spread on prepared pan. Bake in 325°F oven, turning once, until golden, about 20 minutes. Let cool. Reserve 12 walnuts for cake top; finely chop remainder. Set aside.

Maple Butter Icing: In bowl, beat butter until light; gradually beat in sugar and cream, making 3 additions of sugar and 2 of cream. Beat in maple syrup and maple extract. (Make-ahead: Cover and refrigerate for up to 3 days; beat to use.)

Trim tops of cakes to level; cut each cake in half horizontally. Place 1 cake layer, cut side up, on cake plate. Slide strips of waxed paper between cake and plate. Spread cut side with scant 1 cup of the icing; sprinkle with one-third of the chopped walnuts. Cover with remaining cake half, cut side down.

Spread top with another scant 1 cup of the icing and another third of the walnuts. Repeat with remaining cake. Spread scant 1 cup of the icing over top and side to mask and seal in crumbs. Chill until icing is firm, about 30 minutes.

Spread remaining icing over top and side of cake. Remove paper. (Make-ahead: Cover loosely and refrigerate for up to 2 days. Let come to room temperature before serving.) Press reserved walnuts onto cake just before serving.