Your menu doesn’t sound open house friendly. When I think open house I think about things people will pile on a plate and walk around and mingle.

So to me that would eliminate the nachos, mashe dpotatoes, and mac and cheese.

Okay I would only have potato salad Or mashed, and pasta salad OR mac and cheese, nachos Or taco salad.

Just season it with chili powder, seasoned salt, cumin, and garlic powder.

Add a little tomato sauce if you wish, for moisture.

I wouldn’t recomend nachos for an open house though. Nachos are best eaten right away or they get stale and soggy, wich also makes the chip tough.

You could do a toastada bar instead though and leave out the ham.
***And add shredded pork or beef.

Set out the meat, tostada shells, beans, cheese, shreeded lettice, tomatoes, onions, olives, jalapenos, cheese, and of course salsa, sour cream and guac.

Then stick with a pasta salad, and make loaded potato skins.

The desserts sound good.
References :

1 pound ground beef
1 (1 ounce) package taco seasoning mix
3/4 cup water
3/4 pound processed cheese, cubed
1 tablespoon milk
1 (12 ounce) package tortilla chips
1 (16 ounce) can refried beans
1/2 cup chopped fresh tomato
1/3 cup chopped green onions

Place ground beef in a large, deep skillet. Cook over medium high heat until evenly brown. Drain and mix in taco seasoning mix and water. Continue cooking 5 minutes. Remove from heat.
Place processed cheese and milk in a small, microwave safe bowl. Microwave on high until melted, 1 to 2 minutes. Stir until blended and smooth.
Place tortilla chips on a large, microwave safe dish. Spread with refried beans. Top with beef and cheese and mixtures.
Microwave approximately 2 minutes on high, until the cheese has melted into the beef. Top with tomato and green onions. Serve warm.

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Nachos Grande

1 (10.75 ounce) can Cheddar Cheese Soup
1/2 cup Chunky Salsa
1 pound ground beef
1 small onion, chopped
5 cups tortilla chips
1 medium tomatoes, chopped
1 jalapeno pepper, sliced (optional)

Stir the soup and salsa in a 2-quart saucepan.
Cook the beef and onion in a 12-inch skillet over medium-high heat until the beef is well browned, stirring often to separate meat. Pour off any fat. Stir 1/2 cup soup mixture into the skillet. Cook until the beef mixture is hot and bubbling.
Heat the remaining soup mixture over medium heat until it’s hot and bubbling.
Place the chips onto a serving platter and top with the beef mixture. Spoon the soup mixture over the beef mixture. Top with the tomato and jalapeno pepper, if desired.

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Seafood Nachos

30 baked tortilla chips
1 (8 ounce) package imitation crabmeat, chopped
1/4 cup reduced-fat sour cream
1/4 cup reduced-fat mayonnaise
2 tablespoons finely chopped onion
1/4 teaspoon dill weed
1 cup shredded reduced-fat Cheddar cheese
1/4 cup sliced ripe olives
1/4 teaspoon paprika

Arrange tortilla chips in a single layer on an ungreased baking sheet. In a bowl, combine the crab, sour cream, mayonnaise, onion and dill; spoon about 1 tablespoon onto each chip. Sprinkle with cheese, olives and paprika. Bake at 350 degrees F for 6-8 minutes or until cheese is melted.

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References :

an easier way to make nachos is to use nacho cheese sauce (canned)
put it into a crock pot (you may need to add a little water if it is too thick).
make a easy bean dip put taco meat, refried beans, and velvetta cheese into a crock pot and mix well. serve over chips w/nacho cheese
i make this for my parties and everyone loves the bean dip.
your menu is good but i would add salsa also to go with the nachos.
are you going to have some bread to go with the ham? ham/cheese sandwiches. that might be better/easier than mashed potatos and maybe some potato chips instead? just an idea.
References :

Nachos could get a little messy for an open house..
References :

I would suggest lighter fare, finger foods, and cold drinks.

Ham and cheese mini sandwiches
Crackers with thin slices of turkey,cheese and cucumber
Olives and pickles
Fresh fruit cups
One or two salads
The desserts sound very nice

Good luck!
References :

As for teh menu… I don’t think you want taco salad AND nachos, they are too similar. You could probably also skip the mac and cheese if you are also having pasta salad. Maybe replace it with some veggies and dip??

Dessert sounds lovely! Enjoy your open house!!
References :

Your menu sounds delish! What time does the party start?
References :

http://food.yahoo.com/recipes/kraft/52552/velveeta-salsa-dip
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