documentclass[11pt]{book}

usepackage{enumitem, xfrac, xparse}

NewDocumentCommand IngredientList { >{SplitList{;}} m }
 {
begin{description} [noitemsep,leftmargin=!,labelindent=8pt,itemindent=-15pt]
  ProcessList{#1}{ProcessIngredients}
end{description}
 }
newcommandProcessIngredients[1]{item #1}

begin{document}

IngredientList{
4 ounces unsalted butter, room temperature      ;
2 large eggs, room temperature         ;
1 cup granulated sugar         ;
1 tsp. vanilla extract        ;
1 Tbsp. instant espresso powder        ;
sfrac{1}{2} cup cocoa powder, sifted if necessary        ;
1sfrac{1}{2} cups flour       ;
sfrac{1}{2} cup almond flour  ;
1 tsp. baking soda      ;
sfrac{1}{2} tsp. salt  ;
1 cup toasted hazelnuts, roughly chopped (or pistachios or almonds)      ;
3 ounces bittersweet chocolate, coarsely chopped
}
end{document}