Put sugar and water in medium heavy-bottomed saucepan that’s very clean and dry. Stir gently to combine, being careful not to get sugar on sides of saucepan.
Mixture will resemble wet sand. Place saucepan over medium-high heat. Do not stir sugar once it’s on stove. Let sugar come to a boil and cook until golden brown, about seven to eight minutes. Watch carefully, as it can burn quickly. Remove saucepan from heat and slowly whisk in heavy cream. Mixture will bubble up, but will settle down and become caramel. Allow to cool for 10 minutes. Add apple juice.
*Chef’s note: You may make soup up to two days in advance and keep it covered in refrigerator. If soup separates, stir to reblend.
To serve: Heat soup. Slice lemon in half. Cut apple into quarters and remove core from each wedge. Slice quarters into thin, half moon-shaped pieces and place in small mixing bowl. Squeeze lemon juice over slices and gently toss. (Acid will prevent fruit from browning.)
Place about two tablespoons of Pecan Streusel in each of six serving dishes. Place a scoop of French Vanilla Bean Ice Cream on top of streusel. Garnish with apple slices. Soup can be poured table-side or at the last minute before presenting.