Melt 1 stick butter and 3/4 cup chocolate chips over low heat, stirring continually. Add 1 1/2 cups nuts. Sift together 1 1/4 cups plain flour, 1/4 teaspoon salt and 1 1/2 cups sugar. Add 4 eggs, well beaten and 1 teaspoon vanilla. Stir in chocolate mixture and mix well. Pour into lined cupcake pans and bake at 325 degrees for 25 minutes.