wespack.js

const path = require('path');
const webpack = require('webpack');
const ExtractTextPlugin = require("extract-text-webpack-plugin");

const javascript = {
  test: /\.(js)$/,
  use: [{
    loader: 'babel-loader',
    options: { presets: ['es2015'] }
  }],
};

const styles = {
  test: /\.(scss)$/,
  use: ExtractTextPlugin.extract(['style-loader', 'css-loader?sourceMap', 'sass-loader?sourceMap'])
};

const uglify = new webpack.optimize.UglifyJsPlugin({
  compress: { warnings: false }
});

const config = {
  entry: {
    App: './public/javascripts/delicious-app.js'
  },
  devtool: 'source-map',
  output: {
    path: path.resolve(__dirname, 'public', 'javascripts', 'dist'),
    filename: '[name].bundle.js'
  },

  module: {
    rules: [javascript, styles]
  },
  plugins: [
    new ExtractTextPlugin('please-just-make-this-a-file.css'),
  ]
};

module.exports = config;

@wesbos you can use style-loader as fallback loader, if you need.I worked on one webpack setup few days ago and this is how I did it:

{
   test: /\.scss$/,
   use: ExtractTextPlugin.extract({
        fallbackLoader: 'style-loader',
        loader: 'css-loader!sass-loader',
        publicPath: '/public'
    })
}