Preheat oven to 375°F.
Cut the bacon slices in half.
Line a baking sheet with aluminum foil and place a wire rack on top.
Lay the slices of bacon on the wire rack and sprinkle with the brown sugar and some pepper. Press the sugar gently onto the bacon.
Bake the bacon until very brown, about 25 to 30 minutes. Let cool until crisp.
Cut each half slice into 4 pieces. (The bacon can be prepared a day ahead and stored in a sealed plastic bag in the refrigerator. Bring to room temperature before assembling.)
Lightly brush the bread slices with olive oil.
Bake for 8 to 10 minutes or until light brown and crisp. (This can be prepared a day ahead and stored in a sealed plastic bag at room temperature.)
In a small nonstick skillet heat 1 teaspoon of olive oil over medium heat.
Add the shrimp and season with garlic powder and salt.
Cook for about 2 minutes on each side or until pink. Remove from the heat and cool.
Cut the shrimp in half lengthwise. (The shrimp can be made earlier in the day.)
To assemble: ・Place a thin slice of avocado on top of a crostini and sprinkle with Spike seasoning.・Top with 2 pieces of bacon and a shrimp half.・Repeat with the remaining ingredients.
Lightly drizzle with lemon juice and serve.