Step 1: Roast the Sweet Potato

1. Preheat your oven to 400°F (200°C).
2. In a bowl, toss diced sweet potato with 1 tablespoon of olive oil, salt, and pepper.
3. Spread the sweet potato cubes on a baking sheet in a single layer.
4. Roast for 20-25 minutes, or until the sweet potato is tender and lightly browned. Stir halfway through for even cooking.

Step 2: Prepare the Avocado Spread

1. While the sweet potatoes are roasting, cut the avocado in half, remove the pit, and scoop the flesh into a bowl.
2. Add lemon juice, salt, and pepper to the avocado, then mash until smooth. Set aside.

Step 3: Toast the Baguette Slices

1. Heat a grill pan or regular skillet over medium heat.
2. Brush each baguette slice with the remaining 1 tablespoon of olive oil.
3. Toast each side for about 2-3 minutes, until golden brown.
4. Rub the cut side of the garlic clove over the warm baguette slices for added flavor.

Step 4: Assemble the Crostini

1. Spread a generous amount of mashed avocado onto each toasted baguette slice.
2. Top with a few pieces of roasted sweet potato.
3. Sprinkle toasted pumpkin seeds over the top for a crunchy finish.

Step 5: Garnish and Serve

1. Garnish each crostini with chopped parsley and a pinch of red pepper flakes if desired.
2. Serve immediately and enjoy the crispy, creamy, and crunchy layers of this delicious appetizer.