In a small pan, heat up 2 tbsp of olive. Then, add the onion, ½ tbsp garlic salt, and ½ tsp cracked black pepper. Saute that on medium-medium high heat for about 10 minutes until golden.
To make the crostini, In a small bowl combine ¼ cup of olive oil, 1 tbsp garlic salt, and 1 tsp cracked black pepper. Slice up a baguette and place them on a baking sheet lined with a rack. Brush that oil mixture onto each piece of bread and bake them in the oven at 400°F for 5-10 minutes until lightly toasted.
In a separate pan on a low heat, melt the butter. Once the butter is melted, shake in the parmesan cheese and whisk that together until the cheese is melted (make sure you stay on a low heat). Then, add in the drained crab meat and chopped spinach. Stir that together until combined. Lastly, stir in the sauteed onions until everything is combined. *This step is just too warm all the ingredients through. Don't raise the heat too high, once its warmed it is done!
Serve the texas crab grass over the crostini and Enjoy!